665340 has 48 divisors (see below), whose sum is σ = 2008608. Its totient is φ = 163584.

The previous prime is 665311. The next prime is 665351. The reversal of 665340 is 43566.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 665340.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 665340.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 354 + ... + 1206.

It is an arithmetic number, because the mean of its divisors is an integer number (41846).

2⁶⁶⁵³⁴⁰ is an apocalyptic number.

665340 is a gapful number since it is divisible by the number (60) 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 665340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1004304).

665340 is an abundant number, since it is smaller than the sum of its proper divisors (1343268).

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

665340 is a wasteful number, since it uses less digits than its factorization.

665340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 878 (or 876 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 665340 is about 815.6837622510. The cubic root of 665340 is about 87.3000604884.

The spelling of 665340 in words is "six hundred sixty-five thousand, three hundred forty".