165240 has 96 divisors (see below), whose sum is σ = 589680. Its totient is φ = 41472.

The previous prime is 165233. The next prime is 165247. The reversal of 165240 is 42561.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (165233) and next prime (165247).

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165247) by changing a digit.

165240 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9712 + ... + 9728.

2¹⁶⁵²⁴⁰ is an apocalyptic number.

165240 is a gapful number since it is divisible by the number (10) 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 165240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294840).

165240 is an abundant number, since it is smaller than the sum of its proper divisors (424440).

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

165240 is a wasteful number, since it uses less digits than its factorization.

165240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 165240 is about 406.4972324629. The cubic root of 165240 is about 54.8746456426.

165240 divided by its sum of digits (18) gives a triangular number (9180 = T₁₃₅).

The spelling of 165240 in words is "one hundred sixty-five thousand, two hundred forty".