665874 has 64 divisors (see below), whose sum is σ = 1728000. Its totient is φ = 187920.

The previous prime is 665857. The next prime is 665897. The reversal of 665874 is 478566.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 11257 + ... + 11315.

It is an arithmetic number, because the mean of its divisors is an integer number (27000).

2⁶⁶⁵⁸⁷⁴ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665874, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (864000).

665874 is an abundant number, since it is smaller than the sum of its proper divisors (1062126).

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

665874 is a wasteful number, since it uses less digits than its factorization.

665874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100 (or 94 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 665874 is about 816.0110293372. The cubic root of 665874 is about 87.3234098366.

The spelling of 665874 in words is "six hundred sixty-five thousand, eight hundred seventy-four".