25664000 has 80 divisors (see below), whose sum is σ = 64154376. Its totient is φ = 10240000.

The previous prime is 25663993. The next prime is 25664017. The reversal of 25664000 is 46652.

It can be written as a sum of positive squares in 4 ways, for example, as 16128256 + 9535744 = 4016^2 + 3088^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63800 + ... + 64200.

Almost surely, 2^25664000 is an apocalyptic number.

25664000 is a gapful number since it is divisible by the number (20) 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 25664000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32077188).

25664000 is an abundant number, since it is smaller than the sum of its proper divisors (38490376).

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

25664000 is an frugal number, since it uses more digits than its factorization.

25664000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434 (or 408 counting only the distinct ones).

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

The square root of 25664000 is about 5065.9648636760. The cubic root of 25664000 is about 294.9679176065.

The spelling of 25664000 in words is "twenty-five million, six hundred sixty-four thousand".