20881320 has 64 divisors (see below), whose sum is σ = 64350720. Its totient is φ = 5416704.

The previous prime is 20881319. The next prime is 20881331. The reversal of 20881320 is 2318802.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2089 + ... + 6791.

It is an arithmetic number, because the mean of its divisors is an integer number (1005480).

Almost surely, 2^20881320 is an apocalyptic number.

20881320 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 20881320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32175360).

20881320 is an abundant number, since it is smaller than the sum of its proper divisors (43469400).

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

20881320 is a wasteful number, since it uses less digits than its factorization.

20881320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4754 (or 4750 counting only the distinct ones).

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

The square root of 20881320 is about 4569.6082983118. The cubic root of 20881320 is about 275.3717067186.

The spelling of 20881320 in words is "twenty million, eight hundred eighty-one thousand, three hundred twenty".