20878984 has 16 divisors (see below), whose sum is σ = 44740800. Its totient is φ = 8948112.

The previous prime is 20878981. The next prime is 20878987. The reversal of 20878984 is 48987802.

It is an interprime number because it is at equal distance from previous prime (20878981) and next prime (20878987).

It is not an unprimeable number, because it can be changed into a prime (20878981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 186364 + ... + 186475.

It is an arithmetic number, because the mean of its divisors is an integer number (2796300).

Almost surely, 2^20878984 is an apocalyptic number.

It is an amenable number.

20878984 is an abundant number, since it is smaller than the sum of its proper divisors (23861816).

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

20878984 is a wasteful number, since it uses less digits than its factorization.

20878984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372852 (or 372848 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 46.

The square root of 20878984 is about 4569.3526893861. The cubic root of 20878984 is about 275.3614376951.

The spelling of 20878984 in words is "twenty million, eight hundred seventy-eight thousand, nine hundred eighty-four".