64644723 has 40 divisors (see below), whose sum is σ = 113470896. Its totient is φ = 36158400.

The previous prime is 64644691. The next prime is 64644751. The reversal of 64644723 is 32744646.

64644723 is a `hidden beast` number, since 6 + 4 + 644 + 7 + 2 + 3 = 666.

It is not a de Polignac number, because 64644723 - 2⁵ = 64644691 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64642723) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 8793 + ... + 14373.

Almost surely, 2^64644723 is an apocalyptic number.

64644723 is a deficient number, since it is larger than the sum of its proper divisors (48826173).

64644723 is a wasteful number, since it uses less digits than its factorization.

64644723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5617 (or 5608 counting only the distinct ones).

The product of its digits is 96768, while the sum is 36.

The square root of 64644723 is about 8040.1942140722. The cubic root of 64644723 is about 401.3386877067.

It can be divided in two parts, 646 and 44723, that added together give a square (45369 = 213²).

The spelling of 64644723 in words is "sixty-four million, six hundred forty-four thousand, seven hundred twenty-three".