64252805657 has 4 divisors (see below), whose sum is σ = 64287899136. Its totient is φ = 64217712180.

The previous prime is 64252805621. The next prime is 64252805707. The reversal of 64252805657 is 75650825246.

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: 75650825246 = 2 ⋅37825412623.

It is a cyclic number.

It is not a de Polignac number, because 64252805657 - 2²⁰ = 64251757081 is a prime.

It is a super-2 number, since 2×64252805657² (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 (64252805257) 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, 17543993 + ... + 17547654.

It is an arithmetic number, because the mean of its divisors is an integer number (16071974784).

Almost surely, 2^64252805657 is an apocalyptic number.

It is an amenable number.

64252805657 is a deficient number, since it is larger than the sum of its proper divisors (35093479).

64252805657 is a wasteful number, since it uses less digits than its factorization.

64252805657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35093478.

The product of its (nonzero) digits is 4032000, while the sum is 50.

The spelling of 64252805657 in words is "sixty-four billion, two hundred fifty-two million, eight hundred five thousand, six hundred fifty-seven".