165241999 has 4 divisors (see below), whose sum is σ = 177952936. Its totient is φ = 152531064.

The previous prime is 165241957. The next prime is 165242017. The reversal of 165241999 is 999142561.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999142561 = 37 ⋅27003853.

It is a cyclic number.

It is not a de Polignac number, because 165241999 - 2⁷ = 165241871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165241099) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6355449 + ... + 6355474.

It is an arithmetic number, because the mean of its divisors is an integer number (44488234).

Almost surely, 2^165241999 is an apocalyptic number.

165241999 is a deficient number, since it is larger than the sum of its proper divisors (12710937).

165241999 is a wasteful number, since it uses less digits than its factorization.

165241999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12710936.

The product of its digits is 174960, while the sum is 46.

The square root of 165241999 is about 12854.6489255833. The cubic root of 165241999 is about 548.7486692475.

The spelling of 165241999 in words is "one hundred sixty-five million, two hundred forty-one thousand, nine hundred ninety-nine".