55687220 has 24 divisors (see below), whose sum is σ = 120105384. Its totient is φ = 21672576.

The previous prime is 55687213. The next prime is 55687241. The reversal of 55687220 is 2278655.

It can be written as a sum of positive squares in 4 ways, for example, as 20593444 + 35093776 = 4538^2 + 5924^2 .

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, 36887 + ... + 38366.

It is an arithmetic number, because the mean of its divisors is an integer number (5004391).

Almost surely, 2^55687220 is an apocalyptic number.

It is an amenable number.

55687220 is an abundant number, since it is smaller than the sum of its proper divisors (64418164).

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

55687220 is a wasteful number, since it uses less digits than its factorization.

55687220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75299 (or 75297 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 35.

The square root of 55687220 is about 7462.3870175702. The cubic root of 55687220 is about 381.8726126964.

The spelling of 55687220 in words is "fifty-five million, six hundred eighty-seven thousand, two hundred twenty".