261431274502663 has 2 divisors, whose sum is σ = 261431274502664. Its totient is φ = 261431274502662.

The previous prime is 261431274502633. The next prime is 261431274502679. The reversal of 261431274502663 is 366205472134162.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261431274502663 is a prime.

It is a super-2 number, since 2×261431274502663² (a number of 30 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 261431274502663.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261431274502633) 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, 130715637251331 + 130715637251332.

It is an arithmetic number, because the mean of its divisors is an integer number (130715637251332).

Almost surely, 2^{261431274502663} is an apocalyptic number.

261431274502663 is a deficient number, since it is larger than the sum of its proper divisors (1).

261431274502663 is an equidigital number, since it uses as much as digits as its factorization.

261431274502663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8709120, while the sum is 52.

The spelling of 261431274502663 in words is "two hundred sixty-one trillion, four hundred thirty-one billion, two hundred seventy-four million, five hundred two thousand, six hundred sixty-three".