665375 has 8 divisors (see below), whose sum is σ = 830544. Its totient is φ = 532200.

The previous prime is 665369. The next prime is 665381. The reversal of 665375 is 573566.

It is an interprime number because it is at equal distance from previous prime (665369) and next prime (665381).

It is not a de Polignac number, because 665375 - 2⁴ = 665359 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 2537 + ... + 2786.

It is an arithmetic number, because the mean of its divisors is an integer number (103818).

2⁶⁶⁵³⁷⁵ is an apocalyptic number.

665375 is a deficient number, since it is larger than the sum of its proper divisors (165169).

665375 is an equidigital number, since it uses as much as digits as its factorization.

665375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5338 (or 5328 counting only the distinct ones).

The product of its digits is 18900, while the sum is 32.

The square root of 665375 is about 815.7052163619. The cubic root of 665375 is about 87.3015912589.

Subtracting from 665375 its reverse (573566), we obtain a square (91809 = 303²).

The spelling of 665375 in words is "six hundred sixty-five thousand, three hundred seventy-five".