165390 has 32 divisors (see below), whose sum is σ = 410400. Its totient is φ = 42624.

The previous prime is 165383. The next prime is 165391. The reversal of 165390 is 93561.

165390 = 48² + 49² + ... + 84².

It is a self number, because there is not a number n which added to its sum of digits gives 165390.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1036 + ... + 1184.

It is an arithmetic number, because the mean of its divisors is an integer number (12825).

2¹⁶⁵³⁹⁰ is an apocalyptic number.

165390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 165390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (205200).

165390 is an abundant number, since it is smaller than the sum of its proper divisors (245010).

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

165390 is a wasteful number, since it uses less digits than its factorization.

165390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196.

The product of its (nonzero) digits is 810, while the sum is 24.

The square root of 165390 is about 406.6816937114. The cubic root of 165390 is about 54.8912451492.

It can be divided in two parts, 165 and 390, that added together give a palindrome (555).

The spelling of 165390 in words is "one hundred sixty-five thousand, three hundred ninety".