665165501 has 32 divisors (see below), whose sum is σ = 895442688. Its totient is φ = 477181440.

The previous prime is 665165483. The next prime is 665165513. The reversal of 665165501 is 105561566.

It is a cyclic number.

It is not a de Polignac number, because 665165501 - 2⁶ = 665165437 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665165531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 556961 + ... + 558153.

It is an arithmetic number, because the mean of its divisors is an integer number (27982584).

Almost surely, 2^665165501 is an apocalyptic number.

It is an amenable number.

665165501 is a deficient number, since it is larger than the sum of its proper divisors (230277187).

665165501 is a wasteful number, since it uses less digits than its factorization.

665165501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781.

The product of its (nonzero) digits is 27000, while the sum is 35.

The square root of 665165501 is about 25790.8026435782. The cubic root of 665165501 is about 872.9242774663.

The spelling of 665165501 in words is "six hundred sixty-five million, one hundred sixty-five thousand, five hundred one".