165604457 has 2 divisors, whose sum is σ = 165604458. Its totient is φ = 165604456.

The previous prime is 165604433. The next prime is 165604477. The reversal of 165604457 is 754406561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 121793296 + 43811161 = 11036^2 + 6619^2 .

It is an emirp because it is prime and its reverse (754406561) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165604457 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165604457.

It is not a weakly prime, because it can be changed into another prime (165604427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82802228 + 82802229.

It is an arithmetic number, because the mean of its divisors is an integer number (82802229).

Almost surely, 2^165604457 is an apocalyptic number.

It is an amenable number.

165604457 is a deficient number, since it is larger than the sum of its proper divisors (1).

165604457 is an equidigital number, since it uses as much as digits as its factorization.

165604457 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100800, while the sum is 38.

The square root of 165604457 is about 12868.7395264649. The cubic root of 165604457 is about 549.1496026172.

The spelling of 165604457 in words is "one hundred sixty-five million, six hundred four thousand, four hundred fifty-seven".