15664256 has 32 divisors (see below), whose sum is σ = 31808700. Its totient is φ = 7681024.

The previous prime is 15664249. The next prime is 15664261. The reversal of 15664256 is 65246651.

It can be written as a sum of positive squares in 2 ways, for example, as 14318656 + 1345600 = 3784^2 + 1160^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5630 + ... + 7938.

Almost surely, 2^15664256 is an apocalyptic number.

15664256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15664256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15904350).

15664256 is an abundant number, since it is smaller than the sum of its proper divisors (16144444).

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

15664256 is an equidigital number, since it uses as much as digits as its factorization.

15664256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2376 (or 2364 counting only the distinct ones).

The product of its digits is 43200, while the sum is 35.

The square root of 15664256 is about 3957.8094951627. The cubic root of 15664256 is about 250.2091902423.

The spelling of 15664256 in words is "fifteen million, six hundred sixty-four thousand, two hundred fifty-six".