261421716536711 has 2 divisors, whose sum is σ = 261421716536712. Its totient is φ = 261421716536710.

The previous prime is 261421716536647. The next prime is 261421716536723. The reversal of 261421716536711 is 117635617124162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261421716536711 - 2⁶ = 261421716536647 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261421716536731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130710858268355 + 130710858268356.

It is an arithmetic number, because the mean of its divisors is an integer number (130710858268356).

Almost surely, 2^{261421716536711} is an apocalyptic number.

261421716536711 is a deficient number, since it is larger than the sum of its proper divisors (1).

261421716536711 is an equidigital number, since it uses as much as digits as its factorization.

261421716536711 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2540160, while the sum is 53.

The spelling of 261421716536711 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, seven hundred sixteen million, five hundred thirty-six thousand, seven hundred eleven".