25521742136 has 16 divisors (see below), whose sum is σ = 52203563640. Its totient is φ = 11600791840.

The previous prime is 25521742121. The next prime is 25521742139. The reversal of 25521742136 is 63124712552.

It is a self number, because there is not a number n which added to its sum of digits gives 25521742136.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25521742139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 145009811 + ... + 145009986.

Almost surely, 2^25521742136 is an apocalyptic number.

It is an amenable number.

25521742136 is an abundant number, since it is smaller than the sum of its proper divisors (26681821504).

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

25521742136 is a wasteful number, since it uses less digits than its factorization.

25521742136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290019814 (or 290019810 counting only the distinct ones).

The product of its digits is 100800, while the sum is 38.

The spelling of 25521742136 in words is "twenty-five billion, five hundred twenty-one million, seven hundred forty-two thousand, one hundred thirty-six".