166187991600000 has 3456 divisors, whose sum is σ = 682096324291200. Its totient is φ = 40157752320000.

The previous prime is 166187991599957. The next prime is 166187991600077. The reversal of 166187991600000 is 6199781661.

It is a happy number.

166187991600000 is a `hidden beast` number, since 1 + 6 + 618 + 7 + 9 + 9 + 16 + 0 + 0 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (3456).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 166187991600000.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 1553158799947 + ... + 1553158800053.

It is an arithmetic number, because the mean of its divisors is an integer number (197365834575).

Almost surely, 2^{166187991600000} is an apocalyptic number.

166187991600000 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 166187991600000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (341048162145600).

166187991600000 is an abundant number, since it is smaller than the sum of its proper divisors (515908332691200).

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

166187991600000 is an frugal number, since it uses more digits than its factorization.

166187991600000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238 (or 165 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 54.

The spelling of 166187991600000 in words is "one hundred sixty-six trillion, one hundred eighty-seven billion, nine hundred ninety-one million, six hundred thousand".