665615107399 has 16 divisors (see below), whose sum is σ = 769166931456. Its totient is φ = 569267222400.

The previous prime is 665615107393. The next prime is 665615107427. The reversal of 665615107399 is 993701516566.

It is not a de Polignac number, because 665615107399 - 2⁹ = 665615106887 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665615107393) 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 15 ways as a sum of consecutive naturals, for example, 319407 + ... + 1197184.

It is an arithmetic number, because the mean of its divisors is an integer number (48072933216).

Almost surely, 2^665615107399 is an apocalyptic number.

665615107399 is a deficient number, since it is larger than the sum of its proper divisors (103551824057).

665615107399 is a wasteful number, since it uses less digits than its factorization.

665615107399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1518966.

The product of its (nonzero) digits is 9185400, while the sum is 58.

The spelling of 665615107399 in words is "six hundred sixty-five billion, six hundred fifteen million, one hundred seven thousand, three hundred ninety-nine".