# 800 (number)

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800 (number)

800 (eight hundred) is the natural number following 799 and preceding 801.

 Cardinal 800 eight hundred Ordinal 800th eight hundredth Factorization $2^5 \cdot 5^2$ Roman numeral DCCC Roman numeral (Unicode) DCCC, dccc Binary 1100100000 Octal 1440 Duodecimal 568 Hexadecimal 320

It is the sum of four consecutive primes (193 + 197 + 199 + 211). It is a Harshad number.

801 = 32 × 89, Harshad number

802 = 2 × 401, sum of eight consecutive primes (83 + 89 + 97 + 101 + 103 + 107 + 109 + 113), nontotient

803 = 11 × 73, sum of three consecutive primes (263 + 269 + 271), sum of nine consecutive primes (71 + 73 + 79 + 83 + 89 + 97 + 101 + 103 + 107), Harshad number

804 = 22 × 3 × 67, nontotient, Harshad number

805 = 5 × 7 × 23

806 = 2 × 13 × 31, sphenic number, nontotient, totient sum for first 51 integers

807 = 3 × 269

808 = 23 × 101, strobogrammatic number

809 prime number, Sophie Germain prime, Chen prime, Eisenstein prime with no imaginary part

810 = 2 × 34 × 5, Harshad number

811 prime number, sum of five consecutive primes (151 + 157 + 163 + 167 + 173), Chen prime, Mertens function(811) returns 0

812 = 22 × 7 × 29, pronic number, Mertens function(812) returns 0

813 = 3 × 271

814 = 2 × 11 × 37, sphenic number, Mertens function(814) returns 0, nontotient

815 = 5 × 163

816 = 24 × 3 × 17, tetrahedral number, member of the Padovan sequence, Zuckerman number

817 = 19 × 43, sum of three consecutive primes (269 + 271 + 277), centered hexagonal number

818 = 2 × 409, nontotient

819 = 32 × 7 × 13, square pyramidal number

820 = 22 × 5 × 41, triangular number, Harshad number

821 prime number, twin prime, Eisenstein prime with no imaginary part, prime quadruplet with 823, 827, 829

822 = 2 × 3 × 137, sum of twelve consecutive primes (43 + 47 + 53 + 59 + 61 + 67 + 71 + 73 + 79 + 83 + 89 + 97), sphenic number, member of the Mian–Chowla sequence

823 prime number, twin prime, Mertens function(823) returns 0, prime quadruplet with 821, 827, 829

824 = 23 × 103, sum of ten consecutive primes (61 + 67 + 71 + 73 + 79 + 83 + 89 + 97 + 101 + 103), Mertens function(824) returns 0, nontotient

825 = 3 × 52 × 11, Smith number, Mertens function(825) returns 0, Harshad number

826 = 2 × 7 × 59, sphenic number

827 prime number, twin prime, part of prime quadruplet with {821, 823, 829}, sum of seven consecutive primes (103 + 107 + 109 + 113 + 127 + 131 + 137), Chen prime, Eisenstein prime with no imaginary part, strictly non-palindromic number

828 = 22 × 32 × 23, Harshad number

829 prime number, twin prime, part of prime quadruplet with {827, 823, 821}, sum of three consecutive primes (271 + 277 + 281), Chen prime

830 = 2 × 5 × 83, sphenic number, sum of four consecutive primes (197 + 199 + 211 + 223), nontotient, totient sum for first 52 integers

831 = 3 × 277

832 = 26 × 13, Harshad number

833 = 72 × 17

834 = 2 × 3 × 139, sphenic number, sum of six consecutive primes (127 + 131 + 137 + 139 + 149 + 151), nontotient

835 = 5 × 167, Motzkin number

836 = 22 × 11 × 19, weird number

837 = 33 × 31

838 = 2 × 419

839 prime number, safe prime, sum of five consecutive primes (157 + 163 + 167 + 173 + 179), Chen prime, Eisenstein prime with no imaginary part, highly cototient number

840 = 23 × 3 × 5 × 7, highly composite number, smallest numbers divisible by the numbers 1 to 8, sparsely totient number, Harshad number in base 2 through base 10

841 = 292 = 202 + 212, sum of three consecutive primes (277 + 281 + 283), sum of nine consecutive primes (73 + 79 + 83 + 89 + 97 + 101 + 103 + 107 + 109), centered square number, centered heptagonal number, centered octagonal number

842 = 2 × 421, nontotient

843 = 3 × 281

844 = 22 × 211, nontotient

845 = 5 × 132

846 = 2 × 32 × 47, sum of eight consecutive primes (89 + 97 + 101 + 103 + 107 + 109 + 113 + 127), nontotient, Harshad number

847 = 7 × 112

848 = 24 × 53

849 = 3 × 283, Mertens function(849) returns 0

850 = 2 × 52 × 17, Mertens function(850) returns 0, nontotient, the maximum possible Fair Isaac credit score.

851 = 23 × 37

852 = 22 × 3 × 71, Smith number

853 prime number, Mertens function(853) returns 0, average of first 853 prime numbers is an integer (sequence A045345 in OEIS), strictly non-palindromic number

854 = 2 × 7 × 61, nontotient

855 = 32 × 5 × 19, decagonal number, centered cube number

856 = 23 × 107, nonagonal number, centered pentagonal number

857 prime number, sum of three consecutive primes (281 + 283 + 293), Chen prime, Eisenstein prime with no imaginary part

858 = 2 × 3 × 11 × 13, Giuga number

859 prime number

860 = 22 × 5 × 43, sum of four consecutive primes (199 + 211 + 223 + 227)

861 = 3 × 7 × 41, sphenic number, triangular number, hexagonal number, Smith number

862 = 2 × 431

863 prime number, safe prime, sum of five consecutive primes (163 + 167 + 173 + 179 + 181), sum of seven consecutive primes (107 + 109 + 113 + 127 + 131 + 137 + 139), Chen prime, Eisenstein prime with no imaginary part

864 = 25 × 33, sum of a twin prime (431 + 433), sum of six consecutive primes (131 + 137 + 139 + 149 + 151 + 157), Harshad number

865 = 5 × 173

866 = 2 × 433, nontotient

867 = 3 × 172

868 = 22 × 7 × 31, nontotient

869 = 11 × 79, Mertens function(869) returns 0

870 = 2 × 3 × 5 × 29, sum of ten consecutive primes (67 + 71 + 73 + 79 + 83 + 89 + 97 + 101 + 103 + 107), pronic number, nontotient, sparsely totient number, Harshad number

This number is the magic constant of n×n normal magic square and n-queens problem for n = 12.

871 = 13 × 67

872 = 23 × 109, nontotient

873 = 32 × 97, sum of the first six factorials from 1

874 = 2 × 19 × 23, sum of the first twenty-three primes, sum of the first seven factorials from 0, nontotient, Harshad number

875 = 53 × 7

876 = 22 × 3 × 73

877 prime number, Bell number, Chen prime, Mertens function(877) returns 0, strictly non-palindromic number.

878 = 2 × 439, nontotient

879 = 3 × 293

880 = 24 × 5 × 11, Harshad number; 148-gonal number; the number of n×n magic squares for n = 4.

881 prime number, twin prime, sum of nine consecutive primes (79 + 83 + 89 + 97 + 101 + 103 + 107 + 109 + 113), Chen prime, Eisenstein prime with no imaginary part

882 = 2 × 32 × 72, Harshad number, totient sum for first 53 integers

883 prime number, twin prime, sum of three consecutive primes (283 + 293 + 307), Mertens function(883) returns 0

884 = 22 × 13 × 17, Mertens function(884) returns 0

885 = 3 × 5 × 59, sphenic number

886 = 2 × 443, Mertens function(886) returns 0

887 prime number followed by primal gap of 20, safe prime, Chen prime, Eisenstein prime with no imaginary part

888 = 23 × 3 × 37, sum of eight consecutive primes (97 + 101 + 103 + 107 + 109 + 113 + 127 + 131), Harshad number.

889 = 7 × 127, Mertens function(889) returns 0

890 = 2 × 5 × 89, sphenic number, sum of four consecutive primes (211 + 223 + 227 + 229), nontotient

891 = 34 × 11, sum of five consecutive primes (167 + 173 + 179 + 181 + 191), octahedral number

892 = 22 × 223, nontotient

893 = 19 × 47, Mertens function(893) returns 0

894 = 2 × 3 × 149, sphenic number, nontotient

895 = 5 × 179, Smith number, Woodall number, Mertens function(895) returns 0

896 = 27 × 7, sum of six consecutive primes (137 + 139 + 149 + 151 + 157 + 163), Mertens function(896) returns 0

897 = 3 × 13 × 23, sphenic number

898 = 2 × 449, Mertens function(898) returns 0, nontotient

899 = 29 × 31

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• 800 number — ˌātˈhəndrə̇d , dərd noun : a toll free telephone number for long distance calls (as to a business) that is prefixed by the number 800 * * * any toll free telephone number, usually with a 3 digit code of 800, established, as by a business, so that …   Useful english dictionary

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