64131569 has 4 divisors (see below), whose sum is σ = 64263744. Its totient is φ = 63999396.

The previous prime is 64131563. The next prime is 64131601. The reversal of 64131569 is 96513146.

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, and also an emirpimes, since its reverse is a distinct semiprime: 96513146 = 2 ⋅48256573.

It is a cyclic number.

It is not a de Polignac number, because 64131569 - 2⁴ = 64131553 is a prime.

It is a super-2 number, since 2×64131569² = 8225716284803522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64131563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65357 + ... + 66330.

It is an arithmetic number, because the mean of its divisors is an integer number (16065936).

Almost surely, 2^64131569 is an apocalyptic number.

It is an amenable number.

64131569 is a deficient number, since it is larger than the sum of its proper divisors (132175).

64131569 is a wasteful number, since it uses less digits than its factorization.

64131569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132174.

The product of its digits is 19440, while the sum is 35.

The square root of 64131569 is about 8008.2188406661. The cubic root of 64131569 is about 400.2739144677.

The spelling of 64131569 in words is "sixty-four million, one hundred thirty-one thousand, five hundred sixty-nine".