117564581 has 2 divisors, whose sum is σ = 117564582. Its totient is φ = 117564580.

The previous prime is 117564563. The next prime is 117564593. The reversal of 117564581 is 185465711.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92813956 + 24750625 = 9634^2 + 4975^2 .

It is a cyclic number.

It is not a de Polignac number, because 117564581 - 2²² = 113370277 is a prime.

It is a super-2 number, since 2×117564581² = 27642861411411122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen 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 (117561581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 58782290 + 58782291.

It is an arithmetic number, because the mean of its divisors is an integer number (58782291).

Almost surely, 2^117564581 is an apocalyptic number.

It is an amenable number.

117564581 is a deficient number, since it is larger than the sum of its proper divisors (1).

117564581 is an equidigital number, since it uses as much as digits as its factorization.

117564581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 33600, while the sum is 38.

The square root of 117564581 is about 10842.7201845293. The cubic root of 117564581 is about 489.8827721787.

It can be divided in two parts, 1175 and 64581, that added together give a palindrome (65756).

The spelling of 117564581 in words is "one hundred seventeen million, five hundred sixty-four thousand, five hundred eighty-one".