665140 has 24 divisors (see below), whose sum is σ = 1596672. Its totient is φ = 228000.

The previous prime is 665131. The next prime is 665141. The reversal of 665140 is 41566.

665140 = T₁₆₂ + T₁₆₃ + ... + T₂₀₁.

It is a super-2 number, since 2×665140² = 884822439200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2236 + ... + 2515.

It is an arithmetic number, because the mean of its divisors is an integer number (66528).

2⁶⁶⁵¹⁴⁰ is an apocalyptic number.

It is an amenable number.

665140 is an abundant number, since it is smaller than the sum of its proper divisors (931532).

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

665140 is a wasteful number, since it uses less digits than its factorization.

665140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4767 (or 4765 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 665140 is about 815.5611565051. The cubic root of 665140 is about 87.2913121984.

The spelling of 665140 in words is "six hundred sixty-five thousand, one hundred forty".