64644 has 12 divisors (see below), whose sum is σ = 150864. Its totient is φ = 21544.

The previous prime is 64633. The next prime is 64661. The reversal of 64644 is 44646.

64644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a nude number because it is divisible by every one of its digits.

It is a plaindrome in base 13.

It is a nialpdrome in base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 64644.

It is an unprimeable number.

64644 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2682 + ... + 2705.

It is an arithmetic number, because the mean of its divisors is an integer number (12572).

2⁶⁴⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

64644 is an abundant number, since it is smaller than the sum of its proper divisors (86220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75432).

64644 is a wasteful number, since it uses less digits than its factorization.

64644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5394 (or 5392 counting only the distinct ones).

The product of its digits is 2304, while the sum is 24.

The square root of 64644 is about 254.2518436511. The cubic root of 64644 is about 40.1337191483.

Subtracting from 64644 its sum of digits (24), we obtain a triangular number (64620 = T₃₅₉).

The spelling of 64644 in words is "sixty-four thousand, six hundred forty-four".