64972819281 has 4 divisors (see below), whose sum is σ = 86630425712. Its totient is φ = 43315212852.

The previous prime is 64972819279. The next prime is 64972819309. The reversal of 64972819281 is 18291827946.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 64972819281 - 2¹ = 64972819279 is a prime.

It is a super-2 number, since 2×64972819281² (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 (64972819211) 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, 10828803211 + ... + 10828803216.

It is an arithmetic number, because the mean of its divisors is an integer number (21657606428).

Almost surely, 2^64972819281 is an apocalyptic number.

It is an amenable number.

64972819281 is a deficient number, since it is larger than the sum of its proper divisors (21657606431).

64972819281 is a wasteful number, since it uses less digits than its factorization.

64972819281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21657606430.

The product of its digits is 3483648, while the sum is 57.

The spelling of 64972819281 in words is "sixty-four billion, nine hundred seventy-two million, eight hundred nineteen thousand, two hundred eighty-one".