165851913 has 8 divisors (see below), whose sum is σ = 222372000. Its totient is φ = 109949888.

The previous prime is 165851909. The next prime is 165851921. The reversal of 165851913 is 319158561.

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

It is a cyclic number.

It is not a de Polignac number, because 165851913 - 2² = 165851909 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165851923) 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 7 ways as a sum of consecutive naturals, for example, 153888 + ... + 154961.

It is an arithmetic number, because the mean of its divisors is an integer number (27796500).

Almost surely, 2^165851913 is an apocalyptic number.

It is an amenable number.

165851913 is a deficient number, since it is larger than the sum of its proper divisors (56520087).

165851913 is a wasteful number, since it uses less digits than its factorization.

165851913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309031.

The product of its digits is 32400, while the sum is 39.

The square root of 165851913 is about 12878.3505543218. The cubic root of 165851913 is about 549.4229904585.

The spelling of 165851913 in words is "one hundred sixty-five million, eight hundred fifty-one thousand, nine hundred thirteen".