55868521 has 4 divisors (see below), whose sum is σ = 55883844. Its totient is φ = 55853200.

The previous prime is 55868513. The next prime is 55868537. The reversal of 55868521 is 12586855.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 7371225 + 48497296 = 2715^2 + 6964^2 .

It is a cyclic number.

It is not a de Polignac number, because 55868521 - 2³ = 55868513 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55868581) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1311 + ... + 10651.

It is an arithmetic number, because the mean of its divisors is an integer number (13970961).

Almost surely, 2^55868521 is an apocalyptic number.

It is an amenable number.

55868521 is a deficient number, since it is larger than the sum of its proper divisors (15323).

55868521 is an equidigital number, since it uses as much as digits as its factorization.

55868521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15322.

The product of its digits is 96000, while the sum is 40.

The square root of 55868521 is about 7474.5248009489. The cubic root of 55868521 is about 382.2865849219.

The spelling of 55868521 in words is "fifty-five million, eight hundred sixty-eight thousand, five hundred twenty-one".