25660520 has 16 divisors (see below), whose sum is σ = 57736260. Its totient is φ = 10264192.

The previous prime is 25660519. The next prime is 25660541. The reversal of 25660520 is 2506652.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 24186724 + 1473796 = 4918^2 + 1214^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 25660520.

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, 320717 + ... + 320796.

Almost surely, 2^25660520 is an apocalyptic number.

25660520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25660520 is an abundant number, since it is smaller than the sum of its proper divisors (32075740).

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

25660520 is a wasteful number, since it uses less digits than its factorization.

25660520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641524 (or 641520 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 25660520 is about 5065.6213834040. The cubic root of 25660520 is about 294.9545846011.

The spelling of 25660520 in words is "twenty-five million, six hundred sixty thousand, five hundred twenty".