64395152644 has 27 divisors (see below), whose sum is σ = 113479443903. Its totient is φ = 31974012000.

The previous prime is 64395152629. The next prime is 64395152687. The reversal of 64395152644 is 44625159346.

The square root of 64395152644 is 253762.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 4741975044 + 59653177600 = 68862^2 + 244240^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 91861494 + ... + 91862194.

Almost surely, 2^64395152644 is an apocalyptic number.

64395152644 is the 253762-nd square number.

It is an amenable number.

64395152644 is a deficient number, since it is larger than the sum of its proper divisors (49084291259).

64395152644 is an frugal number, since it uses more digits than its factorization.

64395152644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1768 (or 884 counting only the distinct ones).

The product of its digits is 3110400, while the sum is 49.

Multiplying 64395152644 by its sum of digits (49), we get a square (3155362479556 = 1776334²).

The spelling of 64395152644 in words is "sixty-four billion, three hundred ninety-five million, one hundred fifty-two thousand, six hundred forty-four".