665180081405 has 16 divisors (see below), whose sum is σ = 912567080064. Its totient is φ = 455963428800.

The previous prime is 665180081389. The next prime is 665180081407. The reversal of 665180081405 is 504180081566.

It is not a de Polignac number, because 665180081405 - 2⁴ = 665180081389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665180081407) 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, 3233282 + ... + 3432851.

It is an arithmetic number, because the mean of its divisors is an integer number (57035442504).

Almost surely, 2^665180081405 is an apocalyptic number.

It is an amenable number.

665180081405 is a deficient number, since it is larger than the sum of its proper divisors (247386998659).

665180081405 is a wasteful number, since it uses less digits than its factorization.

665180081405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6668996.

The product of its (nonzero) digits is 230400, while the sum is 44.

The spelling of 665180081405 in words is "six hundred sixty-five billion, one hundred eighty million, eighty-one thousand, four hundred five".