25815560 has 64 divisors (see below), whose sum is σ = 60825600. Its totient is φ = 9849600.

The previous prime is 25815553. The next prime is 25815563. The reversal of 25815560 is 6551852.

It is a super-2 number, since 2×25815560² = 1332886276227200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (25815563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135065 + ... + 135255.

It is an arithmetic number, because the mean of its divisors is an integer number (950400).

Almost surely, 2^25815560 is an apocalyptic number.

25815560 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 25815560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30412800).

25815560 is an abundant number, since it is smaller than the sum of its proper divisors (35010040).

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

25815560 is a wasteful number, since it uses less digits than its factorization.

25815560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 32.

The square root of 25815560 is about 5080.9014948137. The cubic root of 25815560 is about 295.5474274518.

The spelling of 25815560 in words is "twenty-five million, eight hundred fifteen thousand, five hundred sixty".