20709719 has 2 divisors, whose sum is σ = 20709720. Its totient is φ = 20709718.

The previous prime is 20709701. The next prime is 20709721. The reversal of 20709719 is 91790702.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20709719 - 2⁸ = 20709463 is a prime.

It is a super-2 number, since 2×20709719² = 857784922117922, which contains 22 as substring.

Together with 20709721, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20709769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10354859 + 10354860.

It is an arithmetic number, because the mean of its divisors is an integer number (10354860).

Almost surely, 2^20709719 is an apocalyptic number.

20709719 is a deficient number, since it is larger than the sum of its proper divisors (1).

20709719 is an equidigital number, since it uses as much as digits as its factorization.

20709719 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7938, while the sum is 35.

The square root of 20709719 is about 4550.7932275593. The cubic root of 20709719 is about 274.6153034225.

The spelling of 20709719 in words is "twenty million, seven hundred nine thousand, seven hundred nineteen".