56660621 has 2 divisors, whose sum is σ = 56660622. Its totient is φ = 56660620.

The previous prime is 56660599. The next prime is 56660623. The reversal of 56660621 is 12606665.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55875625 + 784996 = 7475^2 + 886^2 .

It is a cyclic number.

It is not a de Polignac number, because 56660621 - 2²² = 52466317 is a prime.

Together with 56660623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56660623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28330310 + 28330311.

It is an arithmetic number, because the mean of its divisors is an integer number (28330311).

Almost surely, 2^56660621 is an apocalyptic number.

It is an amenable number.

56660621 is a deficient number, since it is larger than the sum of its proper divisors (1).

56660621 is an equidigital number, since it uses as much as digits as its factorization.

56660621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 56660621 is about 7527.3249564503. The cubic root of 56660621 is about 384.0847907559.

The spelling of 56660621 in words is "fifty-six million, six hundred sixty thousand, six hundred twenty-one".