20512879576639 has 2 divisors, whose sum is σ = 20512879576640. Its totient is φ = 20512879576638.

The previous prime is 20512879576633. The next prime is 20512879576661. The reversal of 20512879576639 is 93667597821502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20512879576639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20512879576633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10256439788319 + 10256439788320.

It is an arithmetic number, because the mean of its divisors is an integer number (10256439788320).

Almost surely, 2^{20512879576639} is an apocalyptic number.

20512879576639 is a deficient number, since it is larger than the sum of its proper divisors (1).

20512879576639 is an equidigital number, since it uses as much as digits as its factorization.

20512879576639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 342921600, while the sum is 70.

The spelling of 20512879576639 in words is "twenty trillion, five hundred twelve billion, eight hundred seventy-nine million, five hundred seventy-six thousand, six hundred thirty-nine".