161938313 has 2 divisors, whose sum is σ = 161938314. Its totient is φ = 161938312.

The previous prime is 161938297. The next prime is 161938367. The reversal of 161938313 is 313839161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123832384 + 38105929 = 11128^2 + 6173^2 .

It is an emirp because it is prime and its reverse (313839161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161938313 - 2⁴ = 161938297 is a prime.

It is not a weakly prime, because it can be changed into another prime (161938393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80969156 + 80969157.

It is an arithmetic number, because the mean of its divisors is an integer number (80969157).

Almost surely, 2^161938313 is an apocalyptic number.

It is an amenable number.

161938313 is a deficient number, since it is larger than the sum of its proper divisors (1).

161938313 is an equidigital number, since it uses as much as digits as its factorization.

161938313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 35.

The square root of 161938313 is about 12725.4985364032. The cubic root of 161938313 is about 545.0669760294.

The spelling of 161938313 in words is "one hundred sixty-one million, nine hundred thirty-eight thousand, three hundred thirteen".