665500 has 48 divisors (see below), whose sum is σ = 1598688. Its totient is φ = 242000.

The previous prime is 665479. The next prime is 665501. The reversal of 665500 is 5566.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

665500 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an Ulam number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665501) 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, 60495 + ... + 60505.

It is an arithmetic number, because the mean of its divisors is an integer number (33306).

2⁶⁶⁵⁵⁰⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (799344).

665500 is an abundant number, since it is smaller than the sum of its proper divisors (933188).

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

665500 is a wasteful number, since it uses less digits than its factorization.

665500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52 (or 18 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 665500 is about 815.7818335805. The cubic root of 665500 is about 87.3070578583.

The spelling of 665500 in words is "six hundred sixty-five thousand, five hundred".