64464442621 has 6 divisors (see below), whose sum is σ = 66253814970. Its totient is φ = 62722159056.

The previous prime is 64464442541. The next prime is 64464442633. The reversal of 64464442621 is 12624446446.

64464442621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 34247573721 + 30216868900 = 185061^2 + 173830^2 .

It is a de Polignac number, because none of the positive numbers 2^k-64464442621 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 (64464442921) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 23542986 + ... + 23545723.

It is an arithmetic number, because the mean of its divisors is an integer number (11042302495).

Almost surely, 2^64464442621 is an apocalyptic number.

It is an amenable number.

64464442621 is a deficient number, since it is larger than the sum of its proper divisors (1789372349).

64464442621 is an equidigital number, since it uses as much as digits as its factorization.

64464442621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47088783 (or 47088746 counting only the distinct ones).

The product of its digits is 884736, while the sum is 43.

The spelling of 64464442621 in words is "sixty-four billion, four hundred sixty-four million, four hundred forty-two thousand, six hundred twenty-one".