644532 has 24 divisors (see below), whose sum is σ = 1718976. Its totient is φ = 184128.

The previous prime is 644531. The next prime is 644549. The reversal of 644532 is 235446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3753 + ... + 3920.

It is an arithmetic number, because the mean of its divisors is an integer number (71624).

2⁶⁴⁴⁵³² is an apocalyptic number.

It is an amenable number.

644532 is an abundant number, since it is smaller than the sum of its proper divisors (1074444).

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

644532 is a wasteful number, since it uses less digits than its factorization.

644532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7687 (or 7685 counting only the distinct ones).

The product of its digits is 2880, while the sum is 24.

The square root of 644532 is about 802.8275032658. The cubic root of 644532 is about 86.3803238802.

Adding to 644532 its reverse (235446), we get a palindrome (879978).

It can be divided in two parts, 644 and 532, that added together give a triangular number (1176 = T₄₈).

The spelling of 644532 in words is "six hundred forty-four thousand, five hundred thirty-two".