64057705521 has 4 divisors (see below), whose sum is σ = 85410274032. Its totient is φ = 42705137012.

The previous prime is 64057705493. The next prime is 64057705529. The reversal of 64057705521 is 12550775046.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 64057705521 - 2⁵ = 64057705489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64057705529) 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, 10676284251 + ... + 10676284256.

It is an arithmetic number, because the mean of its divisors is an integer number (21352568508).

Almost surely, 2^64057705521 is an apocalyptic number.

It is an amenable number.

64057705521 is a deficient number, since it is larger than the sum of its proper divisors (21352568511).

64057705521 is a wasteful number, since it uses less digits than its factorization.

64057705521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21352568510.

The product of its (nonzero) digits is 294000, while the sum is 42.

The spelling of 64057705521 in words is "sixty-four billion, fifty-seven million, seven hundred five thousand, five hundred twenty-one".