100665 has 12 divisors (see below), whose sum is σ = 174564. Its totient is φ = 53664.

The previous prime is 100649. The next prime is 100669. The reversal of 100665 is 566001.

100665 is a `hidden beast` number, since 1 + 0 + 0 + 665 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 59049 + 41616 = 243^2 + 204^2 .

It is not a de Polignac number, because 100665 - 2⁴ = 100649 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 100665.

It is not an unprimeable number, because it can be changed into a prime (100669) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1074 + ... + 1163.

It is an arithmetic number, because the mean of its divisors is an integer number (14547).

2¹⁰⁰⁶⁶⁵ is an apocalyptic number.

100665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

100665 is a deficient number, since it is larger than the sum of its proper divisors (73899).

100665 is a wasteful number, since it uses less digits than its factorization.

100665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2248 (or 2245 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 100665 is about 317.2774810793. The cubic root of 100665 is about 46.5185496579.

Adding to 100665 its reverse (566001), we get a palindrome (666666).

The spelling of 100665 in words is "one hundred thousand, six hundred sixty-five".