51236645591 has 2 divisors, whose sum is σ = 51236645592. Its totient is φ = 51236645590.

The previous prime is 51236645573. The next prime is 51236645641. The reversal of 51236645591 is 19554663215.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51236645591 - 2¹⁰ = 51236644567 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51236645501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25618322795 + 25618322796.

It is an arithmetic number, because the mean of its divisors is an integer number (25618322796).

Almost surely, 2^51236645591 is an apocalyptic number.

51236645591 is a deficient number, since it is larger than the sum of its proper divisors (1).

51236645591 is an equidigital number, since it uses as much as digits as its factorization.

51236645591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 972000, while the sum is 47.

The spelling of 51236645591 in words is "fifty-one billion, two hundred thirty-six million, six hundred forty-five thousand, five hundred ninety-one".