166120205281 has 32 divisors (see below), whose sum is σ = 179160284160. Its totient is φ = 153570707136.

The previous prime is 166120205263. The next prime is 166120205309. The reversal of 166120205281 is 182502021661.

It is a happy number.

166120205281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166120205281 is a prime.

It is a super-2 number, since 2×166120205281² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166120205201) 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 in 31 ways as a sum of consecutive naturals, for example, 41249590 + ... + 41253616.

It is an arithmetic number, because the mean of its divisors is an integer number (5598758880).

Almost surely, 2^166120205281 is an apocalyptic number.

It is an amenable number.

166120205281 is a deficient number, since it is larger than the sum of its proper divisors (13040078879).

166120205281 is a wasteful number, since it uses less digits than its factorization.

166120205281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4453.

The product of its (nonzero) digits is 11520, while the sum is 34.

The spelling of 166120205281 in words is "one hundred sixty-six billion, one hundred twenty million, two hundred five thousand, two hundred eighty-one".