166509786240 has 1024 divisors, whose sum is σ = 723354624000. Its totient is φ = 35350069248.

The previous prime is 166509786239. The next prime is 166509786263. The reversal of 166509786240 is 42687905661.

166509786240 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 0 + 9 + 7 + 8 + 624 + 0 = 666.

166509786240 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 (54).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 121806037 + ... + 121807403.

It is an arithmetic number, because the mean of its divisors is an integer number (706401000).

Almost surely, 2^166509786240 is an apocalyptic number.

166509786240 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 166509786240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (361677312000).

166509786240 is an abundant number, since it is smaller than the sum of its proper divisors (556844837760).

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

166509786240 is a wasteful number, since it uses less digits than its factorization.

166509786240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1474 (or 1456 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 166509786240 in words is "one hundred sixty-six billion, five hundred nine million, seven hundred eighty-six thousand, two hundred forty".