64493356731 has 4 divisors (see below), whose sum is σ = 85991142312. Its totient is φ = 42995571152.

The previous prime is 64493356729. The next prime is 64493356757. The reversal of 64493356731 is 13765339446.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 64493356731 - 2¹ = 64493356729 is a prime.

It is a super-2 number, since 2×64493356731² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64493356721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10748892786 + ... + 10748892791.

It is an arithmetic number, because the mean of its divisors is an integer number (21497785578).

Almost surely, 2^64493356731 is an apocalyptic number.

64493356731 is a deficient number, since it is larger than the sum of its proper divisors (21497785581).

64493356731 is a wasteful number, since it uses less digits than its factorization.

64493356731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21497785580.

The product of its digits is 4898880, while the sum is 51.

The spelling of 64493356731 in words is "sixty-four billion, four hundred ninety-three million, three hundred fifty-six thousand, seven hundred thirty-one".