161915113 has 2 divisors, whose sum is σ = 161915114. Its totient is φ = 161915112.

The previous prime is 161915111. The next prime is 161915129. The reversal of 161915113 is 311519161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81866304 + 80048809 = 9048^2 + 8947^2 .

It is a cyclic number.

It is not a de Polignac number, because 161915113 - 2¹ = 161915111 is a prime.

Together with 161915111, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (161915111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80957556 + 80957557.

It is an arithmetic number, because the mean of its divisors is an integer number (80957557).

Almost surely, 2^161915113 is an apocalyptic number.

It is an amenable number.

161915113 is a deficient number, since it is larger than the sum of its proper divisors (1).

161915113 is an equidigital number, since it uses as much as digits as its factorization.

161915113 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 810, while the sum is 28.

The square root of 161915113 is about 12724.5869481096. The cubic root of 161915113 is about 545.0409452165.

The spelling of 161915113 in words is "one hundred sixty-one million, nine hundred fifteen thousand, one hundred thirteen".