55215760 has 40 divisors (see below), whose sum is σ = 128708280. Its totient is φ = 22029312.

The previous prime is 55215749. The next prime is 55215781. The reversal of 55215760 is 6751255.

It can be written as a sum of positive squares in 4 ways, for example, as 1281424 + 53934336 = 1132^2 + 7344^2 .

It is a tau number, because it is divible by the number of its divisors (40).

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, 44914 + ... + 46126.

It is an arithmetic number, because the mean of its divisors is an integer number (3217707).

Almost surely, 2^55215760 is an apocalyptic number.

It is an amenable number.

55215760 is an abundant number, since it is smaller than the sum of its proper divisors (73492520).

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

55215760 is a wasteful number, since it uses less digits than its factorization.

55215760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1795 (or 1789 counting only the distinct ones).

The product of its (nonzero) digits is 10500, while the sum is 31.

The square root of 55215760 is about 7430.7307850574. The cubic root of 55215760 is about 380.7918851106.

The spelling of 55215760 in words is "fifty-five million, two hundred fifteen thousand, seven hundred sixty".