166186221500 has 192 divisors, whose sum is σ = 403179783552. Its totient is φ = 59443200000.

The previous prime is 166186221451. The next prime is 166186221511. The reversal of 166186221500 is 5122681661.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 60364124 + ... + 60366876.

It is an arithmetic number, because the mean of its divisors is an integer number (2099894706).

Almost surely, 2^166186221500 is an apocalyptic number.

166186221500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166186221500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (201589891776).

166186221500 is an abundant number, since it is smaller than the sum of its proper divisors (236993562052).

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

166186221500 is a wasteful number, since it uses less digits than its factorization.

166186221500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3073 (or 3061 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 38.

The spelling of 166186221500 in words is "one hundred sixty-six billion, one hundred eighty-six million, two hundred twenty-one thousand, five hundred".