20799391 has 2 divisors, whose sum is σ = 20799392. Its totient is φ = 20799390.

The previous prime is 20799377. The next prime is 20799397. The reversal of 20799391 is 19399702.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20799391 - 2⁹ = 20798879 is a prime.

It is a super-2 number, since 2×20799391² = 865229331941762, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20799397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10399695 + 10399696.

It is an arithmetic number, because the mean of its divisors is an integer number (10399696).

Almost surely, 2^20799391 is an apocalyptic number.

20799391 is a deficient number, since it is larger than the sum of its proper divisors (1).

20799391 is an equidigital number, since it uses as much as digits as its factorization.

20799391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30618, while the sum is 40.

The square root of 20799391 is about 4560.6349338661. The cubic root of 20799391 is about 275.0110893600.

The spelling of 20799391 in words is "twenty million, seven hundred ninety-nine thousand, three hundred ninety-one".