55665620 has 12 divisors (see below), whose sum is σ = 116897844. Its totient is φ = 22266240.

The previous prime is 55665601. The next prime is 55665647. The reversal of 55665620 is 2656655.

55665620 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 6160324 + 49505296 = 2482^2 + 7036^2 .

It is a super-2 number, since 2×55665620² = 6197322499968800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1391621 + ... + 1391660.

It is an arithmetic number, because the mean of its divisors is an integer number (9741487).

Almost surely, 2^55665620 is an apocalyptic number.

It is an amenable number.

55665620 is an abundant number, since it is smaller than the sum of its proper divisors (61232224).

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

55665620 is a wasteful number, since it uses less digits than its factorization.

55665620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2783290 (or 2783288 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 35.

The square root of 55665620 is about 7460.9396191096. The cubic root of 55665620 is about 381.8232326343.

The spelling of 55665620 in words is "fifty-five million, six hundred sixty-five thousand, six hundred twenty".