166618673 has 4 divisors (see below), whose sum is σ = 179435508. Its totient is φ = 153801840.

The previous prime is 166618651. The next prime is 166618709. The reversal of 166618673 is 376816661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 25080064 + 141538609 = 5008^2 + 11897^2 .

It is a cyclic number.

It is not a de Polignac number, because 166618673 - 2⁶ = 166618609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166618373) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6408398 + ... + 6408423.

It is an arithmetic number, because the mean of its divisors is an integer number (44858877).

Almost surely, 2^166618673 is an apocalyptic number.

166618673 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

166618673 is a deficient number, since it is larger than the sum of its proper divisors (12816835).

166618673 is a wasteful number, since it uses less digits than its factorization.

166618673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12816834.

The product of its digits is 217728, while the sum is 44.

The square root of 166618673 is about 12908.0855668066. The cubic root of 166618673 is about 550.2683792126.

The spelling of 166618673 in words is "one hundred sixty-six million, six hundred eighteen thousand, six hundred seventy-three".