55721566020 has 24 divisors (see below), whose sum is σ = 156020385024. Its totient is φ = 14859084256.

The previous prime is 55721566013. The next prime is 55721566049. The reversal of 55721566020 is 2066512755.

It is a super-3 number, since 3×55721566020³ (a number of 33 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55721566020.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 464346324 + ... + 464346443.

It is an arithmetic number, because the mean of its divisors is an integer number (6500849376).

Almost surely, 2^55721566020 is an apocalyptic number.

It is an amenable number.

55721566020 is an abundant number, since it is smaller than the sum of its proper divisors (100298819004).

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

55721566020 is a wasteful number, since it uses less digits than its factorization.

55721566020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 928692779 (or 928692777 counting only the distinct ones).

The product of its (nonzero) digits is 126000, while the sum is 39.

The spelling of 55721566020 in words is "fifty-five billion, seven hundred twenty-one million, five hundred sixty-six thousand, twenty".