165664859 has 2 divisors, whose sum is σ = 165664860. Its totient is φ = 165664858.

The previous prime is 165664843. The next prime is 165664871. The reversal of 165664859 is 958466561.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165664859 - 2⁴ = 165664843 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (165664879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82832429 + 82832430.

It is an arithmetic number, because the mean of its divisors is an integer number (82832430).

Almost surely, 2^165664859 is an apocalyptic number.

165664859 is a deficient number, since it is larger than the sum of its proper divisors (1).

165664859 is an equidigital number, since it uses as much as digits as its factorization.

165664859 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1555200, while the sum is 50.

The square root of 165664859 is about 12871.0861624029. The cubic root of 165664859 is about 549.2163594806.

The spelling of 165664859 in words is "one hundred sixty-five million, six hundred sixty-four thousand, eight hundred fifty-nine".