25557987 has 32 divisors (see below), whose sum is σ = 44416512. Its totient is φ = 12685824.

The previous prime is 25557979. The next prime is 25558007. The reversal of 25557987 is 78975552.

It is not a de Polignac number, because 25557987 - 2³ = 25557979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25557947) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1888 + ... + 7394.

It is an arithmetic number, because the mean of its divisors is an integer number (1388016).

Almost surely, 2^25557987 is an apocalyptic number.

25557987 is a deficient number, since it is larger than the sum of its proper divisors (18858525).

25557987 is a wasteful number, since it uses less digits than its factorization.

25557987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5547.

The product of its digits is 882000, while the sum is 48.

The square root of 25557987 is about 5055.4907773628. The cubic root of 25557987 is about 294.5612053468.

The spelling of 25557987 in words is "twenty-five million, five hundred fifty-seven thousand, nine hundred eighty-seven".