161213317 has 2 divisors, whose sum is σ = 161213318. Its totient is φ = 161213316.

The previous prime is 161213287. The next prime is 161213389. The reversal of 161213317 is 713312161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 144024001 + 17189316 = 12001^2 + 4146^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161213317 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 161213291 and 161213300.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161211317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80606658 + 80606659.

It is an arithmetic number, because the mean of its divisors is an integer number (80606659).

Almost surely, 2^161213317 is an apocalyptic number.

It is an amenable number.

161213317 is a deficient number, since it is larger than the sum of its proper divisors (1).

161213317 is an equidigital number, since it uses as much as digits as its factorization.

161213317 is an evil number, because the sum of its binary digits is even.

The product of its digits is 756, while the sum is 25.

The square root of 161213317 is about 12696.9806253298. The cubic root of 161213317 is about 544.2523395441.

Adding to 161213317 its reverse (713312161), we get a palindrome (874525478).

The spelling of 161213317 in words is "one hundred sixty-one million, two hundred thirteen thousand, three hundred seventeen".