165938261 has 8 divisors (see below), whose sum is σ = 179124480. Its totient is φ = 153249712.

The previous prime is 165938251. The next prime is 165938263. The reversal of 165938261 is 162839561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165938261 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 (165938263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123725 + ... + 125058.

It is an arithmetic number, because the mean of its divisors is an integer number (22390560).

Almost surely, 2^165938261 is an apocalyptic number.

It is an amenable number.

165938261 is a deficient number, since it is larger than the sum of its proper divisors (13186219).

165938261 is a wasteful number, since it uses less digits than its factorization.

165938261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248835.

The product of its digits is 77760, while the sum is 41.

The square root of 165938261 is about 12881.7025660430. The cubic root of 165938261 is about 549.5183231857.

The spelling of 165938261 in words is "one hundred sixty-five million, nine hundred thirty-eight thousand, two hundred sixty-one".