20544 has 28 divisors (see below), whose sum is σ = 54864. Its totient is φ = 6784.

The previous prime is 20543. The next prime is 20549. The reversal of 20544 is 44502.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (20543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 139 + ... + 245.

2²⁰⁵⁴⁴ is an apocalyptic number.

20544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27432).

20544 is an abundant number, since it is smaller than the sum of its proper divisors (34320).

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

20544 is a wasteful number, since it uses less digits than its factorization.

20544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 15.

The square root of 20544 is about 143.3317829374. The cubic root of 20544 is about 27.3880851103.

The spelling of 20544 in words is "twenty thousand, five hundred forty-four".