16643802166 has 4 divisors (see below), whose sum is σ = 24965703252. Its totient is φ = 8321901082.

The previous prime is 16643802143. The next prime is 16643802173. The reversal of 16643802166 is 66120834661.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4160950540 + ... + 4160950543.

It is an arithmetic number, because the mean of its divisors is an integer number (6241425813).

Almost surely, 2^16643802166 is an apocalyptic number.

16643802166 is a deficient number, since it is larger than the sum of its proper divisors (8321901086).

16643802166 is an equidigital number, since it uses as much as digits as its factorization.

16643802166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8321901085.

The product of its (nonzero) digits is 248832, while the sum is 43.

The spelling of 16643802166 in words is "sixteen billion, six hundred forty-three million, eight hundred two thousand, one hundred sixty-six".