166399806 has 8 divisors (see below), whose sum is σ = 332799624. Its totient is φ = 55466600.

The previous prime is 166399781. The next prime is 166399817. The reversal of 166399806 is 608993661.

It is a sphenic number, since it is the product of 3 distinct primes.

166399806 is an admirable number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 13866645 + ... + 13866656.

It is an arithmetic number, because the mean of its divisors is an integer number (41599953).

Almost surely, 2^166399806 is an apocalyptic number.

166399806 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166399806 is a wasteful number, since it uses less digits than its factorization.

166399806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27733306.

The product of its (nonzero) digits is 419904, while the sum is 48.

The square root of 166399806 is about 12899.6048776697. The cubic root of 166399806 is about 550.0273330769.

The spelling of 166399806 in words is "one hundred sixty-six million, three hundred ninety-nine thousand, eight hundred six".