165623317 has 2 divisors, whose sum is σ = 165623318. Its totient is φ = 165623316.

The previous prime is 165623303. The next prime is 165623327. The reversal of 165623317 is 713326561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 159542161 + 6081156 = 12631^2 + 2466^2 .

It is an emirp because it is prime and its reverse (713326561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165623317 - 2⁷ = 165623189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165623327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82811658 + 82811659.

It is an arithmetic number, because the mean of its divisors is an integer number (82811659).

Almost surely, 2^165623317 is an apocalyptic number.

It is an amenable number.

165623317 is a deficient number, since it is larger than the sum of its proper divisors (1).

165623317 is an equidigital number, since it uses as much as digits as its factorization.

165623317 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 34.

The square root of 165623317 is about 12869.4722891034. The cubic root of 165623317 is about 549.1704486108.

Adding to 165623317 its reverse (713326561), we get a palindrome (878949878).

The spelling of 165623317 in words is "one hundred sixty-five million, six hundred twenty-three thousand, three hundred seventeen".