165668631 has 8 divisors (see below), whose sum is σ = 224002944. Its totient is φ = 108890040.

The previous prime is 165668627. The next prime is 165668639. The reversal of 165668631 is 136866561.

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

It is not a de Polignac number, because 165668631 - 2² = 165668627 is a prime.

It is a super-2 number, since 2×165668631² = 54892190594828322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165668639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 388681 + ... + 389106.

It is an arithmetic number, because the mean of its divisors is an integer number (28000368).

Almost surely, 2^165668631 is an apocalyptic number.

165668631 is a deficient number, since it is larger than the sum of its proper divisors (58334313).

165668631 is an equidigital number, since it uses as much as digits as its factorization.

165668631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 777861.

The product of its digits is 155520, while the sum is 42.

The square root of 165668631 is about 12871.2326915490. The cubic root of 165668631 is about 549.2205277925.

The spelling of 165668631 in words is "one hundred sixty-five million, six hundred sixty-eight thousand, six hundred thirty-one".