7856 has 10 divisors (see below), whose sum is σ = 15252. Its totient is φ = 3920.

The previous prime is 7853. The next prime is 7867. The reversal of 7856 is 6587.

7856 = T₂₃ + T₂₄ + ... + T₃₈.

It is an alternating number because its digits alternate between odd and even.

It is a plaindrome in base 9 and base 12.

It is not an unprimeable number, because it can be changed into a prime (7853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 230 + ... + 261.

It is an amenable number.

7856 is a deficient number, since it is larger than the sum of its proper divisors (7396).

7856 is a wasteful number, since it uses less digits than its factorization.

7856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499 (or 493 counting only the distinct ones).

The product of its digits is 1680, while the sum is 26.

The square root of 7856 is about 88.6340792246. The cubic root of 7856 is about 19.8792727124.

The spelling of 7856 in words is "seven thousand, eight hundred fifty-six".