25117172540 has 24 divisors (see below), whose sum is σ = 55039370400. Its totient is φ = 9610048448.

The previous prime is 25117172533. The next prime is 25117172543. The reversal of 25117172540 is 4527171152.

It is a self number, because there is not a number n which added to its sum of digits gives 25117172540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25117172543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27300815 + ... + 27301734.

It is an arithmetic number, because the mean of its divisors is an integer number (2293307100).

Almost surely, 2^25117172540 is an apocalyptic number.

25117172540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25117172540 is an abundant number, since it is smaller than the sum of its proper divisors (29922197860).

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

25117172540 is a wasteful number, since it uses less digits than its factorization.

25117172540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54602581 (or 54602579 counting only the distinct ones).

The product of its (nonzero) digits is 19600, while the sum is 35.

The spelling of 25117172540 in words is "twenty-five billion, one hundred seventeen million, one hundred seventy-two thousand, five hundred forty".