20516934979 has 2 divisors, whose sum is σ = 20516934980. Its totient is φ = 20516934978.

The previous prime is 20516934967. The next prime is 20516935013. The reversal of 20516934979 is 97943961502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20516934979 - 2¹⁷ = 20516803907 is a prime.

It is not a weakly prime, because it can be changed into another prime (20516934079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10258467489 + 10258467490.

It is an arithmetic number, because the mean of its divisors is an integer number (10258467490).

Almost surely, 2^20516934979 is an apocalyptic number.

20516934979 is a deficient number, since it is larger than the sum of its proper divisors (1).

20516934979 is an equidigital number, since it uses as much as digits as its factorization.

20516934979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3674160, while the sum is 55.

The spelling of 20516934979 in words is "twenty billion, five hundred sixteen million, nine hundred thirty-four thousand, nine hundred seventy-nine".