64797511681 has 16 divisors (see below), whose sum is σ = 75142166400. Its totient is φ = 54729088128.

The previous prime is 64797511679. The next prime is 64797511699. The reversal of 64797511681 is 18611579746.

It is a cyclic number.

It is not a de Polignac number, because 64797511681 - 2¹ = 64797511679 is a prime.

It is a super-2 number, since 2×64797511681² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64797511601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5050 + ... + 360028.

It is an arithmetic number, because the mean of its divisors is an integer number (4696385400).

Almost surely, 2^64797511681 is an apocalyptic number.

It is an amenable number.

64797511681 is a deficient number, since it is larger than the sum of its proper divisors (10344654719).

64797511681 is a wasteful number, since it uses less digits than its factorization.

64797511681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355368.

The product of its digits is 2540160, while the sum is 55.

The spelling of 64797511681 in words is "sixty-four billion, seven hundred ninety-seven million, five hundred eleven thousand, six hundred eighty-one".