20979883 has 4 divisors (see below), whose sum is σ = 21101328. Its totient is φ = 20858440.

The previous prime is 20979877. The next prime is 20979899. The reversal of 20979883 is 38897902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20979883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20979583) 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, 60463 + ... + 60808.

It is an arithmetic number, because the mean of its divisors is an integer number (5275332).

Almost surely, 2^20979883 is an apocalyptic number.

20979883 is a deficient number, since it is larger than the sum of its proper divisors (121445).

20979883 is a wasteful number, since it uses less digits than its factorization.

20979883 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121444.

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 20979883 is about 4580.3802243919. The cubic root of 20979883 is about 275.8042922260.

The spelling of 20979883 in words is "twenty million, nine hundred seventy-nine thousand, eight hundred eighty-three".