165988631 has 16 divisors (see below), whose sum is σ = 178827264. Its totient is φ = 153694464.

The previous prime is 165988597. The next prime is 165988639. The reversal of 165988631 is 136889561.

165988631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165988631 - 2¹⁰ = 165987607 is a prime.

It is a super-2 number, since 2×165988631² = 55104451242508322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165988639) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104066 + ... + 105648.

It is an arithmetic number, because the mean of its divisors is an integer number (11176704).

Almost surely, 2^165988631 is an apocalyptic number.

165988631 is a deficient number, since it is larger than the sum of its proper divisors (12838633).

165988631 is a wasteful number, since it uses less digits than its factorization.

165988631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1750.

The product of its digits is 311040, while the sum is 47.

The square root of 165988631 is about 12883.6575164043. The cubic root of 165988631 is about 549.5739190393.

The spelling of 165988631 in words is "one hundred sixty-five million, nine hundred eighty-eight thousand, six hundred thirty-one".