168205566643 has 4 divisors (see below), whose sum is σ = 170095516920. Its totient is φ = 166315616368.

The previous prime is 168205566593. The next prime is 168205566653. The reversal of 168205566643 is 346665502861.

168205566643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-168205566643 is a prime.

It is a super-2 number, since 2×168205566643² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (168205566653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 944975005 + ... + 944975182.

It is an arithmetic number, because the mean of its divisors is an integer number (42523879230).

Almost surely, 2^168205566643 is an apocalyptic number.

168205566643 is a deficient number, since it is larger than the sum of its proper divisors (1889950277).

168205566643 is an equidigital number, since it uses as much as digits as its factorization.

168205566643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1889950276.

The product of its (nonzero) digits is 6220800, while the sum is 52.

The spelling of 168205566643 in words is "one hundred sixty-eight billion, two hundred five million, five hundred sixty-six thousand, six hundred forty-three".