161386913 has 2 divisors, whose sum is σ = 161386914. Its totient is φ = 161386912.

The previous prime is 161386903. The next prime is 161386957. The reversal of 161386913 is 319683161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 155176849 + 6210064 = 12457^2 + 2492^2 .

It is a cyclic number.

It is not a de Polignac number, because 161386913 - 2²⁰ = 160338337 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (161386903) 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, 80693456 + 80693457.

It is an arithmetic number, because the mean of its divisors is an integer number (80693457).

Almost surely, 2^161386913 is an apocalyptic number.

It is an amenable number.

161386913 is a deficient number, since it is larger than the sum of its proper divisors (1).

161386913 is an equidigital number, since it uses as much as digits as its factorization.

161386913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 38.

The square root of 161386913 is about 12703.8148994702. The cubic root of 161386913 is about 544.4476214617.

The spelling of 161386913 in words is "one hundred sixty-one million, three hundred eighty-six thousand, nine hundred thirteen".