1999370039665 has 32 divisors (see below), whose sum is σ = 2426854674816. Its totient is φ = 1581189742080.

The previous prime is 1999370039633. The next prime is 1999370039671. The reversal of 1999370039665 is 5669300739991.

It is not a de Polignac number, because 1999370039665 - 2⁵ = 1999370039633 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1999370039665.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 548823334 + ... + 548826976.

It is an arithmetic number, because the mean of its divisors is an integer number (75839208588).

Almost surely, 2^{1999370039665} is an apocalyptic number.

It is an amenable number.

1999370039665 is a deficient number, since it is larger than the sum of its proper divisors (427484635151).

1999370039665 is a wasteful number, since it uses less digits than its factorization.

1999370039665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6769.

The product of its (nonzero) digits is 74401740, while the sum is 67.

The spelling of 1999370039665 in words is "one trillion, nine hundred ninety-nine billion, three hundred seventy million, thirty-nine thousand, six hundred sixty-five".