56136581 has 2 divisors, whose sum is σ = 56136582. Its totient is φ = 56136580.

The previous prime is 56136557. The next prime is 56136599. The reversal of 56136581 is 18563165.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56100100 + 36481 = 7490^2 + 191^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56136581 is a prime.

It is a super-2 number, since 2×56136581² = 6302631452739122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56136541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28068290 + 28068291.

It is an arithmetic number, because the mean of its divisors is an integer number (28068291).

Almost surely, 2^56136581 is an apocalyptic number.

It is an amenable number.

56136581 is a deficient number, since it is larger than the sum of its proper divisors (1).

56136581 is an equidigital number, since it uses as much as digits as its factorization.

56136581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21600, while the sum is 35.

The square root of 56136581 is about 7492.4349179689. The cubic root of 56136581 is about 382.8970198084.

The spelling of 56136581 in words is "fifty-six million, one hundred thirty-six thousand, five hundred eighty-one".