166601786403 has 12 divisors (see below), whose sum is σ = 240537491160. Its totient is φ = 102524175936.

The previous prime is 166601786389. The next prime is 166601786431. The reversal of 166601786403 is 304687106661.

It is not a de Polignac number, because 166601786403 - 2⁶ = 166601786339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166601786443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 164301058 + ... + 164302071.

It is an arithmetic number, because the mean of its divisors is an integer number (20044790930).

Almost surely, 2^166601786403 is an apocalyptic number.

166601786403 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

166601786403 is a deficient number, since it is larger than the sum of its proper divisors (73935704757).

166601786403 is a wasteful number, since it uses less digits than its factorization.

166601786403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328603158 (or 328603145 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 48.

The spelling of 166601786403 in words is "one hundred sixty-six billion, six hundred one million, seven hundred eighty-six thousand, four hundred three".