561059981 has 2 divisors, whose sum is σ = 561059982. Its totient is φ = 561059980.

The previous prime is 561059977. The next prime is 561060007. The reversal of 561059981 is 189950165.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 293573956 + 267486025 = 17134^2 + 16355^2 .

It is a cyclic number.

It is not a de Polignac number, because 561059981 - 2² = 561059977 is a prime.

It is a super-2 number, since 2×561059981² = 629576604559440722, 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 (561052981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280529990 + 280529991.

It is an arithmetic number, because the mean of its divisors is an integer number (280529991).

Almost surely, 2^561059981 is an apocalyptic number.

It is an amenable number.

561059981 is a deficient number, since it is larger than the sum of its proper divisors (1).

561059981 is an equidigital number, since it uses as much as digits as its factorization.

561059981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 97200, while the sum is 44.

The square root of 561059981 is about 23686.7047307134. The cubic root of 561059981 is about 824.7767898131.

The spelling of 561059981 in words is "five hundred sixty-one million, fifty-nine thousand, nine hundred eighty-one".