402656 has 12 divisors (see below), whose sum is σ = 792792. Its totient is φ = 201312.

The previous prime is 402631. The next prime is 402691. The reversal of 402656 is 656204.

It is an Ulam number.

It is a plaindrome in base 13.

It is a congruent number.

It is an unprimeable number.

402656 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 6260 + ... + 6323.

It is an arithmetic number, because the mean of its divisors is an integer number (66066).

2⁴⁰²⁶⁵⁶ is an apocalyptic number.

It is an amenable number.

402656 is a deficient number, since it is larger than the sum of its proper divisors (390136).

402656 is a wasteful number, since it uses less digits than its factorization.

402656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12593 (or 12585 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 402656 is about 634.5518103355. The cubic root of 402656 is about 73.8433501428.

It can be divided in two parts, 4026 and 56, that multiplied together give a triangular number (225456 = T₆₇₁).

The spelling of 402656 in words is "four hundred two thousand, six hundred fifty-six".