20850 has 24 divisors (see below), whose sum is σ = 52080. Its totient is φ = 5520.

The previous prime is 20849. The next prime is 20857. The reversal of 20850 is 5802.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (20857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81 + ... + 219.

It is an arithmetic number, because the mean of its divisors is an integer number (2170).

2²⁰⁸⁵⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26040).

20850 is an abundant number, since it is smaller than the sum of its proper divisors (31230).

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

20850 is a wasteful number, since it uses less digits than its factorization.

20850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 20850 is about 144.3952907819. The cubic root of 20850 is about 27.5233960677.

The spelling of 20850 in words is "twenty thousand, eight hundred fifty".