166720861520928 has 576 divisors, whose sum is σ = 599950344913920. Its totient is φ = 43153254144000.

The previous prime is 166720861520921. The next prime is 166720861520977. The reversal of 166720861520928 is 829025168027661.

166720861520928 is a `hidden beast` number, since 1 + 6 + 6 + 7 + 2 + 0 + 8 + 615 + 2 + 0 + 9 + 2 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (166720861520921) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 31169853 + ... + 36124803.

It is an arithmetic number, because the mean of its divisors is an integer number (1041580459920).

Almost surely, 2^{166720861520928} is an apocalyptic number.

166720861520928 is a gapful number since it is divisible by the number (18) 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 166720861520928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (299975172456960).

166720861520928 is an abundant number, since it is smaller than the sum of its proper divisors (433229483392992).

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

166720861520928 is a wasteful number, since it uses less digits than its factorization.

166720861520928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4955053 (or 4955042 counting only the distinct ones).

The product of its (nonzero) digits is 34836480, while the sum is 63.

It can be divided in two parts, 1667208 and 61520928, that added together give a palindrome (63188136).

The spelling of 166720861520928 in words is "one hundred sixty-six trillion, seven hundred twenty billion, eight hundred sixty-one million, five hundred twenty thousand, nine hundred twenty-eight".