166064661840 has 1280 divisors, whose sum is σ = 733118791680. Its totient is φ = 30005821440.

The previous prime is 166064661779. The next prime is 166064661863. The reversal of 166064661840 is 48166460661.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 166064661840.

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 255 ways as a sum of consecutive naturals, for example, 256668397 + ... + 256669043.

It is an arithmetic number, because the mean of its divisors is an integer number (572749056).

Almost surely, 2^166064661840 is an apocalyptic number.

166064661840 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 166064661840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (366559395840).

166064661840 is an abundant number, since it is smaller than the sum of its proper divisors (567054129840).

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

166064661840 is a wasteful number, since it uses less digits than its factorization.

166064661840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760 (or 754 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 48.

The spelling of 166064661840 in words is "one hundred sixty-six billion, sixty-four million, six hundred sixty-one thousand, eight hundred forty".