165491437 has 2 divisors, whose sum is σ = 165491438. Its totient is φ = 165491436.

The previous prime is 165491419. The next prime is 165491441. The reversal of 165491437 is 734194561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 156900676 + 8590761 = 12526^2 + 2931^2 .

It is a cyclic number.

It is not a de Polignac number, because 165491437 - 2²⁷ = 31273709 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165491437.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165491537) 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, 82745718 + 82745719.

It is an arithmetic number, because the mean of its divisors is an integer number (82745719).

Almost surely, 2^165491437 is an apocalyptic number.

It is an amenable number.

165491437 is a deficient number, since it is larger than the sum of its proper divisors (1).

165491437 is an equidigital number, since it uses as much as digits as its factorization.

165491437 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 165491437 is about 12864.3475155175. The cubic root of 165491437 is about 549.0246482254.

The spelling of 165491437 in words is "one hundred sixty-five million, four hundred ninety-one thousand, four hundred thirty-seven".