166728222361 has 2 divisors, whose sum is σ = 166728222362. Its totient is φ = 166728222360.

The previous prime is 166728222301. The next prime is 166728222407. The reversal of 166728222361 is 163222827661.

166728222361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (166728222407) can be obtained adding 166728222361 to its sum of digits (46).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165267453961 + 1460768400 = 406531^2 + 38220^2 .

It is an emirp because it is prime and its reverse (163222827661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166728222361 - 2³¹ = 164580738713 is a prime.

It is not a weakly prime, because it can be changed into another prime (166728222301) by changing a digit.

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 as a sum of consecutive naturals, namely, 83364111180 + 83364111181.

It is an arithmetic number, because the mean of its divisors is an integer number (83364111181).

Almost surely, 2^166728222361 is an apocalyptic number.

It is an amenable number.

166728222361 is a deficient number, since it is larger than the sum of its proper divisors (1).

166728222361 is an equidigital number, since it uses as much as digits as its factorization.

166728222361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 580608, while the sum is 46.

The spelling of 166728222361 in words is "one hundred sixty-six billion, seven hundred twenty-eight million, two hundred twenty-two thousand, three hundred sixty-one".