1680604515665 has 8 divisors (see below), whose sum is σ = 2016756201768. Its totient is φ = 1344463090560.

The previous prime is 1680604515659. The next prime is 1680604515739. The reversal of 1680604515665 is 5665154060861.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 145503339601 + 1535101176064 = 381449^2 + 1238992^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1680604515665 - 2⁴ = 1680604515649 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2200196 + ... + 2863925.

It is an arithmetic number, because the mean of its divisors is an integer number (252094525221).

Almost surely, 2^{1680604515665} is an apocalyptic number.

It is an amenable number.

1680604515665 is a deficient number, since it is larger than the sum of its proper divisors (336151686103).

1680604515665 is an equidigital number, since it uses as much as digits as its factorization.

1680604515665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5130499.

The product of its (nonzero) digits is 5184000, while the sum is 53.

The spelling of 1680604515665 in words is "one trillion, six hundred eighty billion, six hundred four million, five hundred fifteen thousand, six hundred sixty-five".