20979443 has 2 divisors, whose sum is σ = 20979444. Its totient is φ = 20979442.

The previous prime is 20979433. The next prime is 20979461. The reversal of 20979443 is 34497902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20979443 - 2⁸ = 20979187 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 20979397 and 20979406.

It is not a weakly prime, because it can be changed into another prime (20979403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10489721 + 10489722.

It is an arithmetic number, because the mean of its divisors is an integer number (10489722).

Almost surely, 2^20979443 is an apocalyptic number.

20979443 is a deficient number, since it is larger than the sum of its proper divisors (1).

20979443 is an equidigital number, since it uses as much as digits as its factorization.

20979443 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 20979443 is about 4580.3321931930. The cubic root of 20979443 is about 275.8023641133.

The spelling of 20979443 in words is "twenty million, nine hundred seventy-nine thousand, four hundred forty-three".