20188320 has 96 divisors (see below), whose sum is σ = 64266048. Its totient is φ = 5326848.

The previous prime is 20188307. The next prime is 20188327. The reversal of 20188320 is 2388102.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (20188327) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65607 + ... + 65913.

It is an arithmetic number, because the mean of its divisors is an integer number (669438).

Almost surely, 2^20188320 is an apocalyptic number.

20188320 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 20188320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32133024).

20188320 is an abundant number, since it is smaller than the sum of its proper divisors (44077728).

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

20188320 is a wasteful number, since it uses less digits than its factorization.

20188320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462 (or 454 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 20188320 is about 4493.1414400172. The cubic root of 20188320 is about 272.2910667349.

The spelling of 20188320 in words is "twenty million, one hundred eighty-eight thousand, three hundred twenty".