165252121 has 16 divisors (see below), whose sum is σ = 183340800. Its totient is φ = 148232448.

The previous prime is 165252107. The next prime is 165252133. The reversal of 165252121 is 121252561.

It is a cyclic number.

It is not a de Polignac number, because 165252121 - 2⁷ = 165251993 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165252161) 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 in 15 ways as a sum of consecutive naturals, for example, 36826 + ... + 41068.

It is an arithmetic number, because the mean of its divisors is an integer number (11458800).

Almost surely, 2^165252121 is an apocalyptic number.

It is an amenable number.

165252121 is a deficient number, since it is larger than the sum of its proper divisors (18088679).

165252121 is a wasteful number, since it uses less digits than its factorization.

165252121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4368.

The product of its digits is 1200, while the sum is 25.

The square root of 165252121 is about 12855.0426292564. The cubic root of 165252121 is about 548.7598736641.

The spelling of 165252121 in words is "one hundred sixty-five million, two hundred fifty-two thousand, one hundred twenty-one".