25515138516 has 24 divisors (see below), whose sum is σ = 68040369600. Its totient is φ = 7290039552.

The previous prime is 25515138487. The next prime is 25515138547. The reversal of 25515138516 is 61583151552.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151875741 + ... + 151875908.

It is an arithmetic number, because the mean of its divisors is an integer number (2835015400).

Almost surely, 2^25515138516 is an apocalyptic number.

It is an amenable number.

25515138516 is an abundant number, since it is smaller than the sum of its proper divisors (42525231084).

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

25515138516 is a wasteful number, since it uses less digits than its factorization.

25515138516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303751663 (or 303751661 counting only the distinct ones).

The product of its digits is 180000, while the sum is 42.

The spelling of 25515138516 in words is "twenty-five billion, five hundred fifteen million, one hundred thirty-eight thousand, five hundred sixteen".