64356805621 has 8 divisors (see below), whose sum is σ = 65282212440. Its totient is φ = 63432582912.

The previous prime is 64356805619. The next prime is 64356805637. The reversal of 64356805621 is 12650865346.

It can be written as a sum of positive squares in 4 ways, for example, as 20796524100 + 43560281521 = 144210^2 + 208711^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 64356805621 - 2¹ = 64356805619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64356845621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 186256 + ... + 404233.

It is an arithmetic number, because the mean of its divisors is an integer number (8160276555).

Almost surely, 2^64356805621 is an apocalyptic number.

It is an amenable number.

64356805621 is a deficient number, since it is larger than the sum of its proper divisors (925406819).

64356805621 is a wasteful number, since it uses less digits than its factorization.

64356805621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 592055.

The product of its (nonzero) digits is 1036800, while the sum is 46.

The spelling of 64356805621 in words is "sixty-four billion, three hundred fifty-six million, eight hundred five thousand, six hundred twenty-one".