1660080905209 has 4 divisors (see below), whose sum is σ = 1687295346340. Its totient is φ = 1632866464080.

The previous prime is 1660080905191. The next prime is 1660080905213. The reversal of 1660080905209 is 9025090800661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 161728644025 + 1498352261184 = 402155^2 + 1224072^2 .

It is a cyclic number.

It is not a de Polignac number, because 1660080905209 - 2¹³ = 1660080897017 is a prime.

It is a super-2 number, since 2×1660080905209² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1660080905309) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13607220474 + ... + 13607220595.

It is an arithmetic number, because the mean of its divisors is an integer number (421823836585).

Almost surely, 2^{1660080905209} is an apocalyptic number.

It is an amenable number.

1660080905209 is a deficient number, since it is larger than the sum of its proper divisors (27214441131).

1660080905209 is an equidigital number, since it uses as much as digits as its factorization.

1660080905209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27214441130.

The product of its (nonzero) digits is 233280, while the sum is 46.

The spelling of 1660080905209 in words is "one trillion, six hundred sixty billion, eighty million, nine hundred five thousand, two hundred nine".