20888840 has 64 divisors (see below), whose sum is σ = 54639360. Its totient is φ = 7038720.

The previous prime is 20888797. The next prime is 20888863. The reversal of 20888840 is 4888802.

It is a junction number, because it is equal to n+sod(n) for n = 20888794 and 20888803.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16469 + ... + 17691.

It is an arithmetic number, because the mean of its divisors is an integer number (853740).

Almost surely, 2^20888840 is an apocalyptic number.

20888840 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 20888840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27319680).

20888840 is an abundant number, since it is smaller than the sum of its proper divisors (33750520).

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

20888840 is a wasteful number, since it uses less digits than its factorization.

20888840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1302 (or 1298 counting only the distinct ones).

The product of its (nonzero) digits is 32768, while the sum is 38.

The square root of 20888840 is about 4570.4310518812. The cubic root of 20888840 is about 275.4047593337.

Subtracting from 20888840 its sum of digits (38), we obtain a palindrome (20888802).

The spelling of 20888840 in words is "twenty million, eight hundred eighty-eight thousand, eight hundred forty".