247113257561 has 2 divisors, whose sum is σ = 247113257562. Its totient is φ = 247113257560.

The previous prime is 247113257527. The next prime is 247113257591. The reversal of 247113257561 is 165752311742.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209197379161 + 37915878400 = 457381^2 + 194720^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-247113257561 is a prime.

It is a super-2 number, since 2×247113257561² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (247113257591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123556628780 + 123556628781.

It is an arithmetic number, because the mean of its divisors is an integer number (123556628781).

Almost surely, 2^247113257561 is an apocalyptic number.

It is an amenable number.

247113257561 is a deficient number, since it is larger than the sum of its proper divisors (1).

247113257561 is an equidigital number, since it uses as much as digits as its factorization.

247113257561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 352800, while the sum is 44.

The spelling of 247113257561 in words is "two hundred forty-seven billion, one hundred thirteen million, two hundred fifty-seven thousand, five hundred sixty-one".