55131613520 has 20 divisors (see below), whose sum is σ = 128181001620. Its totient is φ = 22052645376.

The previous prime is 55131613517. The next prime is 55131613543. The reversal of 55131613520 is 2531613155.

It can be written as a sum of positive squares in 2 ways, for example, as 22617753664 + 32513859856 = 150392^2 + 180316^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 344572505 + ... + 344572664.

It is an arithmetic number, because the mean of its divisors is an integer number (6409050081).

Almost surely, 2^55131613520 is an apocalyptic number.

It is an amenable number.

55131613520 is an abundant number, since it is smaller than the sum of its proper divisors (73049388100).

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

55131613520 is a wasteful number, since it uses less digits than its factorization.

55131613520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689145182 (or 689145176 counting only the distinct ones).

The product of its (nonzero) digits is 13500, while the sum is 32.

The spelling of 55131613520 in words is "fifty-five billion, one hundred thirty-one million, six hundred thirteen thousand, five hundred twenty".