51630316511561 has 2 divisors, whose sum is σ = 51630316511562. Its totient is φ = 51630316511560.

The previous prime is 51630316511551. The next prime is 51630316511663. The reversal of 51630316511561 is 16511561303615.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51249405359161 + 380911152400 = 7158869^2 + 617180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51630316511561 is a prime.

It is not a weakly prime, because it can be changed into another prime (51630316511551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25815158255780 + 25815158255781.

It is an arithmetic number, because the mean of its divisors is an integer number (25815158255781).

Almost surely, 2^{51630316511561} is an apocalyptic number.

It is an amenable number.

51630316511561 is a deficient number, since it is larger than the sum of its proper divisors (1).

51630316511561 is an equidigital number, since it uses as much as digits as its factorization.

51630316511561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 243000, while the sum is 44.

The spelling of 51630316511561 in words is "fifty-one trillion, six hundred thirty billion, three hundred sixteen million, five hundred eleven thousand, five hundred sixty-one".