165138912 has 84 divisors (see below), whose sum is σ = 487521720. Its totient is φ = 55038528.

The previous prime is 165138893. The next prime is 165138917. The reversal of 165138912 is 219831561.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165138917) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 19789 + ... + 26867.

It is an arithmetic number, because the mean of its divisors is an integer number (5803830).

Almost surely, 2^165138912 is an apocalyptic number.

165138912 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165138912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243760860).

165138912 is an abundant number, since it is smaller than the sum of its proper divisors (322382808).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165138912 is an frugal number, since it uses more digits than its factorization.

165138912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7107 (or 7084 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The square root of 165138912 is about 12850.6385833545. The cubic root of 165138912 is about 548.6345323612.

It can be divided in two parts, 16513 and 8912, that added together give a triangular number (25425 = T₂₂₅).

The spelling of 165138912 in words is "one hundred sixty-five million, one hundred thirty-eight thousand, nine hundred twelve".