20900 has 36 divisors (see below), whose sum is σ = 52080. Its totient is φ = 7200.

The previous prime is 20899. The next prime is 20903. The reversal of 20900 is 902.

20900 = 16² + 17² + ... + 40².

It is a Harshad number since it is a multiple of its sum of digits (11).

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (20903) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1091 + ... + 1109.

2²⁰⁹⁰⁰ is an apocalyptic number.

20900 is a gapful number since it is divisible by the number (20) 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 20900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26040).

20900 is an abundant number, since it is smaller than the sum of its proper divisors (31180).

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

20900 is a wasteful number, since it uses less digits than its factorization.

20900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44 (or 37 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 20900 is about 144.5683229480. The cubic root of 20900 is about 27.5453796203.

The spelling of 20900 in words is "twenty thousand, nine hundred".