55666561499 has 4 divisors (see below), whose sum is σ = 55738575936. Its totient is φ = 55594547064.

The previous prime is 55666561481. The next prime is 55666561507. The reversal of 55666561499 is 99416566655.

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 55666561499 - 2¹² = 55666557403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55666561799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36006059 + ... + 36007604.

It is an arithmetic number, because the mean of its divisors is an integer number (13934643984).

Almost surely, 2^55666561499 is an apocalyptic number.

55666561499 is a deficient number, since it is larger than the sum of its proper divisors (72014437).

55666561499 is an equidigital number, since it uses as much as digits as its factorization.

55666561499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72014436.

The product of its digits is 52488000, while the sum is 62.

The spelling of 55666561499 in words is "fifty-five billion, six hundred sixty-six million, five hundred sixty-one thousand, four hundred ninety-nine".