166681818216 has 48 divisors (see below), whose sum is σ = 466996479300. Its totient is φ = 53644722432.

The previous prime is 166681818211. The next prime is 166681818227. The reversal of 166681818216 is 612818186661.

It can be written as a sum of positive squares in 2 ways, for example, as 144745246116 + 21936572100 = 380454^2 + 148110^2 .

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (166681818211) 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, 39912141 + ... + 39916316.

Almost surely, 2^166681818216 is an apocalyptic number.

It is an amenable number.

166681818216 is an abundant number, since it is smaller than the sum of its proper divisors (300314661084).

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

166681818216 is a wasteful number, since it uses less digits than its factorization.

166681818216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79828498 (or 79828491 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 54.

The spelling of 166681818216 in words is "one hundred sixty-six billion, six hundred eighty-one million, eight hundred eighteen thousand, two hundred sixteen".