165021673 has 2 divisors, whose sum is σ = 165021674. Its totient is φ = 165021672.

The previous prime is 165021671. The next prime is 165021691. The reversal of 165021673 is 376120561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 156425049 + 8596624 = 12507^2 + 2932^2 .

It is a cyclic number.

It is not a de Polignac number, because 165021673 - 2¹ = 165021671 is a prime.

Together with 165021671, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (165021671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82510836 + 82510837.

It is an arithmetic number, because the mean of its divisors is an integer number (82510837).

Almost surely, 2^165021673 is an apocalyptic number.

It is an amenable number.

165021673 is a deficient number, since it is larger than the sum of its proper divisors (1).

165021673 is an equidigital number, since it uses as much as digits as its factorization.

165021673 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 165021673 is about 12846.0761713451. The cubic root of 165021673 is about 548.5046687803.

The spelling of 165021673 in words is "one hundred sixty-five million, twenty-one thousand, six hundred seventy-three".