55551868520 has 32 divisors (see below), whose sum is σ = 125003907720. Its totient is φ = 22218577920.

The previous prime is 55551868457. The next prime is 55551868549. The reversal of 55551868520 is 2586815555.

It can be written as a sum of positive squares in 4 ways, for example, as 44814349636 + 10737518884 = 211694^2 + 103622^2 .

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, 384224 + ... + 508656.

Almost surely, 2^55551868520 is an apocalyptic number.

It is an amenable number.

55551868520 is an abundant number, since it is smaller than the sum of its proper divisors (69452039200).

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

55551868520 is a wasteful number, since it uses less digits than its factorization.

55551868520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135605 (or 135601 counting only the distinct ones).

The product of its (nonzero) digits is 2400000, while the sum is 50.

The spelling of 55551868520 in words is "fifty-five billion, five hundred fifty-one million, eight hundred sixty-eight thousand, five hundred twenty".