64787991131 has 16 divisors (see below), whose sum is σ = 66352897440. Its totient is φ = 63236609280.

The previous prime is 64787991127. The next prime is 64787991133. The reversal of 64787991131 is 13119978746.

It is a cyclic number.

It is not a de Polignac number, because 64787991131 - 2² = 64787991127 is a prime.

It is a super-2 number, since 2×64787991131² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64787991133) 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 in 15 ways as a sum of consecutive naturals, for example, 8971040 + ... + 8978258.

It is an arithmetic number, because the mean of its divisors is an integer number (4147056090).

Almost surely, 2^64787991131 is an apocalyptic number.

64787991131 is a deficient number, since it is larger than the sum of its proper divisors (1564906309).

64787991131 is a wasteful number, since it uses less digits than its factorization.

64787991131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8126.

The product of its digits is 2286144, while the sum is 56.

The spelling of 64787991131 in words is "sixty-four billion, seven hundred eighty-seven million, nine hundred ninety-one thousand, one hundred thirty-one".