665655601 has 16 divisors (see below), whose sum is σ = 735799680. Its totient is φ = 598429440.

The previous prime is 665655593. The next prime is 665655611. The reversal of 665655601 is 106556566.

665655601 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 665655601 - 2³ = 665655593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665655611) 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, 72265 + ... + 80953.

It is an arithmetic number, because the mean of its divisors is an integer number (45987480).

Almost surely, 2^665655601 is an apocalyptic number.

It is an amenable number.

665655601 is a deficient number, since it is larger than the sum of its proper divisors (70144079).

665655601 is a wasteful number, since it uses less digits than its factorization.

665655601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8856.

The product of its (nonzero) digits is 162000, while the sum is 40.

The square root of 665655601 is about 25800.3023431897. The cubic root of 665655601 is about 873.1386176853.

The spelling of 665655601 in words is "six hundred sixty-five million, six hundred fifty-five thousand, six hundred one".