665341660405 has 16 divisors (see below), whose sum is σ = 812020464000. Its totient is φ = 523201416640.

The previous prime is 665341660397. The next prime is 665341660421. The reversal of 665341660405 is 504066143566.

It is a happy number.

It is not a de Polignac number, because 665341660405 - 2³ = 665341660397 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3126960 + ... + 3332950.

It is an arithmetic number, because the mean of its divisors is an integer number (50751279000).

Almost surely, 2^665341660405 is an apocalyptic number.

It is an amenable number.

665341660405 is a deficient number, since it is larger than the sum of its proper divisors (146678803595).

665341660405 is a wasteful number, since it uses less digits than its factorization.

665341660405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217004.

The product of its (nonzero) digits is 1555200, while the sum is 46.

The spelling of 665341660405 in words is "six hundred sixty-five billion, three hundred forty-one million, six hundred sixty thousand, four hundred five".