161317313 has 4 divisors (see below), whose sum is σ = 162153348. Its totient is φ = 160481280.

The previous prime is 161317309. The next prime is 161317327. The reversal of 161317313 is 313713161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 69022864 + 92294449 = 8308^2 + 9607^2 .

It is a cyclic number.

It is not a de Polignac number, because 161317313 - 2² = 161317309 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161317333) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 417728 + ... + 418113.

It is an arithmetic number, because the mean of its divisors is an integer number (40538337).

Almost surely, 2^161317313 is an apocalyptic number.

It is an amenable number.

161317313 is a deficient number, since it is larger than the sum of its proper divisors (836035).

161317313 is an equidigital number, since it uses as much as digits as its factorization.

161317313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 836034.

The product of its digits is 1134, while the sum is 26.

The square root of 161317313 is about 12701.0752694408. The cubic root of 161317313 is about 544.3693437327.

The spelling of 161317313 in words is "one hundred sixty-one million, three hundred seventeen thousand, three hundred thirteen".