656438 has 16 divisors (see below), whose sum is σ = 1069200. Its totient is φ = 301056.

The previous prime is 656429. The next prime is 656459. The reversal of 656438 is 834656.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

656438 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 in 7 ways as a sum of consecutive naturals, for example, 1238 + ... + 1686.

It is an arithmetic number, because the mean of its divisors is an integer number (66825).

2⁶⁵⁶⁴³⁸ is an apocalyptic number.

656438 is a deficient number, since it is larger than the sum of its proper divisors (412762).

656438 is a wasteful number, since it uses less digits than its factorization.

656438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511.

The product of its digits is 17280, while the sum is 32.

The square root of 656438 is about 810.2086151109. The cubic root of 656438 is about 86.9089636538.

The spelling of 656438 in words is "six hundred fifty-six thousand, four hundred thirty-eight".