56686691 has 2 divisors, whose sum is σ = 56686692. Its totient is φ = 56686690.

The previous prime is 56686657. The next prime is 56686711. The reversal of 56686691 is 19668665.

56686691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56686691 is a prime.

It is not a weakly prime, because it can be changed into another prime (56689691) by changing a digit.

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 as a sum of consecutive naturals, namely, 28343345 + 28343346.

It is an arithmetic number, because the mean of its divisors is an integer number (28343346).

Almost surely, 2^56686691 is an apocalyptic number.

56686691 is a deficient number, since it is larger than the sum of its proper divisors (1).

56686691 is an equidigital number, since it uses as much as digits as its factorization.

56686691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 466560, while the sum is 47.

The square root of 56686691 is about 7529.0564481879. The cubic root of 56686691 is about 384.1436885407.

The spelling of 56686691 in words is "fifty-six million, six hundred eighty-six thousand, six hundred ninety-one".