20643932719 has 2 divisors, whose sum is σ = 20643932720. Its totient is φ = 20643932718.

The previous prime is 20643932671. The next prime is 20643932731. The reversal of 20643932719 is 91723934602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20643932719 is a prime.

It is a super-2 number, since 2×20643932719² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20643932759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10321966359 + 10321966360.

It is an arithmetic number, because the mean of its divisors is an integer number (10321966360).

Almost surely, 2^20643932719 is an apocalyptic number.

20643932719 is a deficient number, since it is larger than the sum of its proper divisors (1).

20643932719 is an equidigital number, since it uses as much as digits as its factorization.

20643932719 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 489888, while the sum is 46.

The spelling of 20643932719 in words is "twenty billion, six hundred forty-three million, nine hundred thirty-two thousand, seven hundred nineteen".