20986878 has 16 divisors (see below), whose sum is σ = 45789696. Its totient is φ = 6359640.

The previous prime is 20986871. The next prime is 20986883. The reversal of 20986878 is 87868902.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20986871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 158926 + ... + 159057.

It is an arithmetic number, because the mean of its divisors is an integer number (2861856).

Almost surely, 2^20986878 is an apocalyptic number.

20986878 is an abundant number, since it is smaller than the sum of its proper divisors (24802818).

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

20986878 is a wasteful number, since it uses less digits than its factorization.

20986878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317999.

The product of its (nonzero) digits is 387072, while the sum is 48.

The square root of 20986878 is about 4581.1437436518. The cubic root of 20986878 is about 275.8349412157.

The spelling of 20986878 in words is "twenty million, nine hundred eighty-six thousand, eight hundred seventy-eight".