20830979 has 4 divisors (see below), whose sum is σ = 22433376. Its totient is φ = 19228584.

The previous prime is 20830949. The next prime is 20830991. The reversal of 20830979 is 97903802.

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

It is a cyclic number.

It is not a de Polignac number, because 20830979 - 2²⁰ = 19782403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20830949) 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, 801179 + ... + 801204.

It is an arithmetic number, because the mean of its divisors is an integer number (5608344).

Almost surely, 2^20830979 is an apocalyptic number.

20830979 is a deficient number, since it is larger than the sum of its proper divisors (1602397).

20830979 is a wasteful number, since it uses less digits than its factorization.

20830979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1602396.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 20830979 is about 4564.0967342947. The cubic root of 20830979 is about 275.1502385676.

The spelling of 20830979 in words is "twenty million, eight hundred thirty thousand, nine hundred seventy-nine".