165851489 has 2 divisors, whose sum is σ = 165851490. Its totient is φ = 165851488.

The previous prime is 165851479. The next prime is 165851509. The reversal of 165851489 is 984158561.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112678225 + 53173264 = 10615^2 + 7292^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165851489 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (165851449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82925744 + 82925745.

It is an arithmetic number, because the mean of its divisors is an integer number (82925745).

Almost surely, 2^165851489 is an apocalyptic number.

It is an amenable number.

165851489 is a deficient number, since it is larger than the sum of its proper divisors (1).

165851489 is an equidigital number, since it uses as much as digits as its factorization.

165851489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 345600, while the sum is 47.

The square root of 165851489 is about 12878.3340925758. The cubic root of 165851489 is about 549.4225222586.

The spelling of 165851489 in words is "one hundred sixty-five million, eight hundred fifty-one thousand, four hundred eighty-nine".