7857

7857 is a positive integer that follows 7856 and precedes 7858. In decimal notation, its digits are 7, 8, 5, and 7, giving the common spoken form seven thousand eight hundred fifty-seven.

Mathematically, 7857 is a composite number with prime factorization 3^4 × 97, since 7857 = 81 × 97. Its divisors are 1, 3, 9, 27, 81, 97, 291, 873, 2619, and 7857, reflecting the total of ten divisors. The number is divisible by 3, 9, 27, and 81, but not by 2, 5, or 7. Because the sum of its digits is 27, which divides 7857 evenly (7857 ÷ 27 = 291), it is a Harshad (Niven) number in base 10. The sum of all divisors, including 7857 itself, is 11,858, making the sum of proper divisors 4,001. Since 4,001 < 7,857, 7857 is a deficient number.

In other bases, 7857 has the representations 1111010110001 in binary, 17261 in octal, and 1EB1 in hexadecimal (base 16). The hexadecimal form corresponds to 1 × 4096 + 14 × 256 + 11 × 16 + 1 = 7857.

Overall, 7857 is a modestly composite, base-10 Harshad number with a straightforward factorization and small set of divisors, and it admits standard representations in binary, octal, and hexadecimal.