644124 has 24 divisors (see below), whose sum is σ = 1618960. Its totient is φ = 198144.

The previous prime is 644123. The next prime is 644129. The reversal of 644124 is 421446.

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

It is a self number, because there is not a number n which added to its sum of digits gives 644124.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644123) 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, 1909 + ... + 2220.

2⁶⁴⁴¹²⁴ is an apocalyptic number.

It is an amenable number.

644124 is an abundant number, since it is smaller than the sum of its proper divisors (974836).

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

644124 is a wasteful number, since it uses less digits than its factorization.

644124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4149 (or 4147 counting only the distinct ones).

The product of its digits is 768, while the sum is 21.

The square root of 644124 is about 802.5733611328. The cubic root of 644124 is about 86.3620932823.

The spelling of 644124 in words is "six hundred forty-four thousand, one hundred twenty-four".