165221778960 has 180 divisors, whose sum is σ = 645460934508. Its totient is φ = 37764969984.

The previous prime is 165221778949. The next prime is 165221778989. The reversal of 165221778960 is 69877122561.

165221778960 is a `hidden beast` number, since 16 + 522 + 17 + 7 + 8 + 96 + 0 = 666.

165221778960 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 113631016464 + 51590762496 = 337092^2 + 227136^2 .

It is a tau number, because it is divible by the number of its divisors (180).

It is a junction number, because it is equal to n+sod(n) for n = 165221778897 and 165221778906.

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 35 ways as a sum of consecutive naturals, for example, 2306299 + ... + 2376858.

Almost surely, 2^165221778960 is an apocalyptic number.

165221778960 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165221778960 is an abundant number, since it is smaller than the sum of its proper divisors (480239155548).

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

165221778960 is a wasteful number, since it uses less digits than its factorization.

165221778960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4683190 (or 4683174 counting only the distinct ones).

The product of its (nonzero) digits is 2540160, while the sum is 54.

The spelling of 165221778960 in words is "one hundred sixty-five billion, two hundred twenty-one million, seven hundred seventy-eight thousand, nine hundred sixty".