561637231 has 2 divisors, whose sum is σ = 561637232. Its totient is φ = 561637230.

The previous prime is 561637183. The next prime is 561637247. The reversal of 561637231 is 132736165.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 561637231 - 2¹⁹ = 561112943 is a prime.

It is a super-2 number, since 2×561637231² = 630872758490694722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561637831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280818615 + 280818616.

It is an arithmetic number, because the mean of its divisors is an integer number (280818616).

Almost surely, 2^561637231 is an apocalyptic number.

561637231 is a deficient number, since it is larger than the sum of its proper divisors (1).

561637231 is an equidigital number, since it uses as much as digits as its factorization.

561637231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 34.

The square root of 561637231 is about 23698.8867038095. The cubic root of 561637231 is about 825.0595517465.

The spelling of 561637231 in words is "five hundred sixty-one million, six hundred thirty-seven thousand, two hundred thirty-one".