561972491 has 2 divisors, whose sum is σ = 561972492. Its totient is φ = 561972490.

The previous prime is 561972487. The next prime is 561972511. The reversal of 561972491 is 194279165.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 561972491 - 2² = 561972487 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (561972401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280986245 + 280986246.

It is an arithmetic number, because the mean of its divisors is an integer number (280986246).

Almost surely, 2^561972491 is an apocalyptic number.

561972491 is a deficient number, since it is larger than the sum of its proper divisors (1).

561972491 is an equidigital number, since it uses as much as digits as its factorization.

561972491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 44.

The square root of 561972491 is about 23705.9589765949. The cubic root of 561972491 is about 825.2236876152.

The spelling of 561972491 in words is "five hundred sixty-one million, nine hundred seventy-two thousand, four hundred ninety-one".