81793152013 has 2 divisors, whose sum is σ = 81793152014. Its totient is φ = 81793152012.

The previous prime is 81793151983. The next prime is 81793152017. The reversal of 81793152013 is 31025139718.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81406361124 + 386790889 = 285318^2 + 19667^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81793152013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81793152017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40896576006 + 40896576007.

It is an arithmetic number, because the mean of its divisors is an integer number (40896576007).

Almost surely, 2^81793152013 is an apocalyptic number.

It is an amenable number.

81793152013 is a deficient number, since it is larger than the sum of its proper divisors (1).

81793152013 is an equidigital number, since it uses as much as digits as its factorization.

81793152013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 40.

The spelling of 81793152013 in words is "eighty-one billion, seven hundred ninety-three million, one hundred fifty-two thousand, thirteen".