166021306560 has 560 divisors, whose sum is σ = 625948313760. Its totient is φ = 41695395840.

The previous prime is 166021306541. The next prime is 166021306567. The reversal of 166021306560 is 65603120661.

166021306560 is a `hidden beast` number, since 1 + 6 + 60 + 2 + 1 + 30 + 6 + 560 = 666.

166021306560 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (166021306567) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 30816187 + ... + 30821573.

It is an arithmetic number, because the mean of its divisors is an integer number (1117764846).

Almost surely, 2^166021306560 is an apocalyptic number.

166021306560 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 166021306560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312974156880).

166021306560 is an abundant number, since it is smaller than the sum of its proper divisors (459927007200).

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

166021306560 is a wasteful number, since it uses less digits than its factorization.

166021306560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5486 (or 5467 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The spelling of 166021306560 in words is "one hundred sixty-six billion, twenty-one million, three hundred six thousand, five hundred sixty".