22656640 has 32 divisors (see below), whose sum is σ = 54165060. Its totient is φ = 9062400.

The previous prime is 22656637. The next prime is 22656659. The reversal of 22656640 is 4665622.

It can be written as a sum of positive squares in 2 ways, for example, as 21455424 + 1201216 = 4632^2 + 1096^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17061 + ... + 18340.

Almost surely, 2^22656640 is an apocalyptic number.

22656640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22656640 is an abundant number, since it is smaller than the sum of its proper divisors (31508420).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22656640 is an equidigital number, since it uses as much as digits as its factorization.

22656640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35420 (or 35408 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 22656640 is about 4759.8991585957. The cubic root of 22656640 is about 282.9644226024.

The spelling of 22656640 in words is "twenty-two million, six hundred fifty-six thousand, six hundred forty".