56720591 has 2 divisors, whose sum is σ = 56720592. Its totient is φ = 56720590.

The previous prime is 56720557. The next prime is 56720611. The reversal of 56720591 is 19502765.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56720591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56726591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28360295 + 28360296.

It is an arithmetic number, because the mean of its divisors is an integer number (28360296).

Almost surely, 2^56720591 is an apocalyptic number.

56720591 is a deficient number, since it is larger than the sum of its proper divisors (1).

56720591 is an equidigital number, since it uses as much as digits as its factorization.

56720591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 56720591 is about 7531.3073898228. The cubic root of 56720591 is about 384.2202489923.

The spelling of 56720591 in words is "fifty-six million, seven hundred twenty thousand, five hundred ninety-one".