20949984719 has 2 divisors, whose sum is σ = 20949984720. Its totient is φ = 20949984718.

The previous prime is 20949984703. The next prime is 20949984739. The reversal of 20949984719 is 91748994902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20949984719 - 2⁴ = 20949984703 is a prime.

It is a super-2 number, since 2×20949984719² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20949984739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10474992359 + 10474992360.

It is an arithmetic number, because the mean of its divisors is an integer number (10474992360).

Almost surely, 2^20949984719 is an apocalyptic number.

20949984719 is a deficient number, since it is larger than the sum of its proper divisors (1).

20949984719 is an equidigital number, since it uses as much as digits as its factorization.

20949984719 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11757312, while the sum is 62.

The spelling of 20949984719 in words is "twenty billion, nine hundred forty-nine million, nine hundred eighty-four thousand, seven hundred nineteen".