1566808989899 has 4 divisors (see below), whose sum is σ = 1567593573264. Its totient is φ = 1566024406536.

The previous prime is 1566808989881. The next prime is 1566808989923. The reversal of 1566808989899 is 9989898086651.

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

It is a cyclic number.

It is not a de Polignac number, because 1566808989899 - 2¹⁶ = 1566808924363 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 1566808989899.

It is not an unprimeable number, because it can be changed into a prime (1566808919899) 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, 392288687 + ... + 392292680.

It is an arithmetic number, because the mean of its divisors is an integer number (391898393316).

Almost surely, 2^{1566808989899} is an apocalyptic number.

1566808989899 is a deficient number, since it is larger than the sum of its proper divisors (784583365).

1566808989899 is an equidigital number, since it uses as much as digits as its factorization.

1566808989899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 784583364.

The product of its (nonzero) digits is 4837294080, while the sum is 86.

The spelling of 1566808989899 in words is "one trillion, five hundred sixty-six billion, eight hundred eight million, nine hundred eighty-nine thousand, eight hundred ninety-nine".