9915972013 has 2 divisors, whose sum is σ = 9915972014. Its totient is φ = 9915972012.

The previous prime is 9915971993. The next prime is 9915972023. The reversal of 9915972013 is 3102795199.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6972584004 + 2943388009 = 83502^2 + 54253^2 .

It is a cyclic number.

It is not a de Polignac number, because 9915972013 - 2²⁵ = 9882417581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9915972023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4957986006 + 4957986007.

It is an arithmetic number, because the mean of its divisors is an integer number (4957986007).

Almost surely, 2^9915972013 is an apocalyptic number.

It is an amenable number.

9915972013 is a deficient number, since it is larger than the sum of its proper divisors (1).

9915972013 is an equidigital number, since it uses as much as digits as its factorization.

9915972013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 153090, while the sum is 46.

The square root of 9915972013 is about 99578.9737494819. The cubic root of 9915972013 is about 2148.3832816554.

The spelling of 9915972013 in words is "nine billion, nine hundred fifteen million, nine hundred seventy-two thousand, thirteen".