20979858 has 16 divisors (see below), whose sum is σ = 42023520. Its totient is φ = 6982656.

The previous prime is 20979809. The next prime is 20979877. The reversal of 20979858 is 85897902.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2341 + ... + 6887.

It is an arithmetic number, because the mean of its divisors is an integer number (2626470).

Almost surely, 2^20979858 is an apocalyptic number.

20979858 is an abundant number, since it is smaller than the sum of its proper divisors (21043662).

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

20979858 is a wasteful number, since it uses less digits than its factorization.

20979858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5321.

The product of its (nonzero) digits is 362880, while the sum is 48.

The square root of 20979858 is about 4580.3774953600. The cubic root of 20979858 is about 275.8041826749.

The spelling of 20979858 in words is "twenty million, nine hundred seventy-nine thousand, eight hundred fifty-eight".