64494591631 has 2 divisors, whose sum is σ = 64494591632. Its totient is φ = 64494591630.

The previous prime is 64494591547. The next prime is 64494591739. The reversal of 64494591631 is 13619549446.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64494591631 - 2²⁹ = 63957720719 is a prime.

It is a super-2 number, since 2×64494591631² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64494591131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32247295815 + 32247295816.

It is an arithmetic number, because the mean of its divisors is an integer number (32247295816).

Almost surely, 2^64494591631 is an apocalyptic number.

64494591631 is a deficient number, since it is larger than the sum of its proper divisors (1).

64494591631 is an equidigital number, since it uses as much as digits as its factorization.

64494591631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2799360, while the sum is 52.

The spelling of 64494591631 in words is "sixty-four billion, four hundred ninety-four million, five hundred ninety-one thousand, six hundred thirty-one".