20879910 has 64 divisors (see below), whose sum is σ = 58968000. Its totient is φ = 5239296.

The previous prime is 20879909. The next prime is 20879921. The reversal of 20879910 is 1997802.

It is a happy number.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 2316 + ... + 6864.

It is an arithmetic number, because the mean of its divisors is an integer number (921375).

Almost surely, 2^20879910 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20879910, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29484000).

20879910 is an abundant number, since it is smaller than the sum of its proper divisors (38088090).

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

20879910 is a wasteful number, since it uses less digits than its factorization.

20879910 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4582 (or 4576 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 20879910 is about 4569.4540155253. The cubic root of 20879910 is about 275.3655084699.

The spelling of 20879910 in words is "twenty million, eight hundred seventy-nine thousand, nine hundred ten".