25171591990 has 32 divisors (see below), whose sum is σ = 45530952480. Its totient is φ = 10019407104.

The previous prime is 25171591987. The next prime is 25171592041. The reversal of 25171591990 is 9919517152.

It is a super-2 number, since 2×25171591990² (a number of 22 digits) contains 22 as substring.

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, 1724764 + ... + 1739296.

It is an arithmetic number, because the mean of its divisors is an integer number (1422842265).

Almost surely, 2^25171591990 is an apocalyptic number.

25171591990 is a deficient number, since it is larger than the sum of its proper divisors (20359360490).

25171591990 is a wasteful number, since it uses less digits than its factorization.

25171591990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15376.

The product of its (nonzero) digits is 255150, while the sum is 49.

The spelling of 25171591990 in words is "twenty-five billion, one hundred seventy-one million, five hundred ninety-one thousand, nine hundred ninety".