166501323026666 has 16 divisors (see below), whose sum is σ = 258459354073800. Its totient is φ = 80350321271808.

The previous prime is 166501323026639. The next prime is 166501323026681. The reversal of 166501323026666 is 666620323105661.

It can be written as a sum of positive squares in 4 ways, for example, as 139136863505641 + 27364459521025 = 11795629^2 + 5231105^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 528908711 + ... + 529223418.

Almost surely, 2^{166501323026666} is an apocalyptic number.

166501323026666 is a deficient number, since it is larger than the sum of its proper divisors (91958031047134).

166501323026666 is a wasteful number, since it uses less digits than its factorization.

166501323026666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058134873.

The product of its (nonzero) digits is 8398080, while the sum is 53.

The spelling of 166501323026666 in words is "one hundred sixty-six trillion, five hundred one billion, three hundred twenty-three million, twenty-six thousand, six hundred sixty-six".