20680979 has 16 divisors (see below), whose sum is σ = 24102144. Its totient is φ = 17556000.

The previous prime is 20680967. The next prime is 20680981. The reversal of 20680979 is 97908602.

It is not a de Polignac number, because 20680979 - 2⁴ = 20680963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20682979) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9929 + ... + 11829.

It is an arithmetic number, because the mean of its divisors is an integer number (1506384).

Almost surely, 2^20680979 is an apocalyptic number.

20680979 is a deficient number, since it is larger than the sum of its proper divisors (3421165).

20680979 is a wasteful number, since it uses less digits than its factorization.

20680979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1978.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 20680979 is about 4547.6344400138. The cubic root of 20680979 is about 274.4882117647.

The spelling of 20680979 in words is "twenty million, six hundred eighty thousand, nine hundred seventy-nine".