20601979 has 2 divisors, whose sum is σ = 20601980. Its totient is φ = 20601978.

The previous prime is 20601961. The next prime is 20601983. The reversal of 20601979 is 97910602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20601979 - 2⁷ = 20601851 is a prime.

It is not a weakly prime, because it can be changed into another prime (20601929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10300989 + 10300990.

It is an arithmetic number, because the mean of its divisors is an integer number (10300990).

Almost surely, 2^20601979 is an apocalyptic number.

20601979 is a deficient number, since it is larger than the sum of its proper divisors (1).

20601979 is an equidigital number, since it uses as much as digits as its factorization.

20601979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 20601979 is about 4538.9402948265. The cubic root of 20601979 is about 274.1382567216.

The spelling of 20601979 in words is "twenty million, six hundred one thousand, nine hundred seventy-nine".