538644 has 12 divisors (see below), whose sum is σ = 1256864. Its totient is φ = 179544.

The previous prime is 538621. The next prime is 538649. The reversal of 538644 is 446835.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (538649) by changing a digit.

538644 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, 22432 + ... + 22455.

2⁵³⁸⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

538644 is an abundant number, since it is smaller than the sum of its proper divisors (718220).

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

538644 is a wasteful number, since it uses less digits than its factorization.

538644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44894 (or 44892 counting only the distinct ones).

The product of its digits is 11520, while the sum is 30.

The square root of 538644 is about 733.9237017565. The cubic root of 538644 is about 81.3643093216.

Subtracting from 538644 its reverse (446835), we obtain a square (91809 = 303²).

The spelling of 538644 in words is "five hundred thirty-eight thousand, six hundred forty-four".