665361 has 16 divisors (see below), whose sum is σ = 1038400. Its totient is φ = 419904.

The previous prime is 665359. The next prime is 665369. The reversal of 665361 is 163566.

665361 is a `hidden beast` number, since 6 + 653 + 6 + 1 = 666.

It is not a de Polignac number, because 665361 - 2¹ = 665359 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a plaindrome in base 14.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 665361.

It is not an unprimeable number, because it can be changed into a prime (665369) 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, 136 + ... + 1161.

It is an arithmetic number, because the mean of its divisors is an integer number (64900).

2⁶⁶⁵³⁶¹ is an apocalyptic number.

It is an amenable number.

665361 is a deficient number, since it is larger than the sum of its proper divisors (373039).

665361 is a wasteful number, since it uses less digits than its factorization.

665361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1325 (or 1319 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 665361 is about 815.6966347853. The cubic root of 665361 is about 87.3009789571.

The spelling of 665361 in words is "six hundred sixty-five thousand, three hundred sixty-one".