25515540 has 48 divisors (see below), whose sum is σ = 79383360. Its totient is φ = 6804000.

The previous prime is 25515509. The next prime is 25515551. The reversal of 25515540 is 4551552.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23086 + ... + 24165.

It is an arithmetic number, because the mean of its divisors is an integer number (1653820).

Almost surely, 2^25515540 is an apocalyptic number.

25515540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25515540 is an abundant number, since it is smaller than the sum of its proper divisors (53867820).

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

25515540 is a wasteful number, since it uses less digits than its factorization.

25515540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47269 (or 47261 counting only the distinct ones).

The product of its (nonzero) digits is 5000, while the sum is 27.

The square root of 25515540 is about 5051.2909241104. The cubic root of 25515540 is about 294.3980447698.

The spelling of 25515540 in words is "twenty-five million, five hundred fifteen thousand, five hundred forty".