20188820 has 24 divisors (see below), whose sum is σ = 42491904. Its totient is φ = 8057376.

The previous prime is 20188799. The next prime is 20188823. The reversal of 20188820 is 2888102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20188823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11309 + ... + 12971.

It is an arithmetic number, because the mean of its divisors is an integer number (1770496).

Almost surely, 2^20188820 is an apocalyptic number.

20188820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20188820 is an abundant number, since it is smaller than the sum of its proper divisors (22303084).

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

20188820 is a wasteful number, since it uses less digits than its factorization.

20188820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2279 (or 2277 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 29.

The square root of 20188820 is about 4493.1970800311. The cubic root of 20188820 is about 272.2933146421.

The spelling of 20188820 in words is "twenty million, one hundred eighty-eight thousand, eight hundred twenty".