15681113813 has 2 divisors, whose sum is σ = 15681113814. Its totient is φ = 15681113812.

The previous prime is 15681113809. The next prime is 15681113821. The reversal of 15681113813 is 31831118651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8185363729 + 7495750084 = 90473^2 + 86578^2 .

It is an emirp because it is prime and its reverse (31831118651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15681113813 - 2² = 15681113809 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15681113863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7840556906 + 7840556907.

It is an arithmetic number, because the mean of its divisors is an integer number (7840556907).

Almost surely, 2^15681113813 is an apocalyptic number.

It is an amenable number.

15681113813 is a deficient number, since it is larger than the sum of its proper divisors (1).

15681113813 is an equidigital number, since it uses as much as digits as its factorization.

15681113813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 38.

The spelling of 15681113813 in words is "fifteen billion, six hundred eighty-one million, one hundred thirteen thousand, eight hundred thirteen".