166541281 has 2 divisors, whose sum is σ = 166541282. Its totient is φ = 166541280.

The previous prime is 166541267. The next prime is 166541359. The reversal of 166541281 is 182145661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 156650256 + 9891025 = 12516^2 + 3145^2 .

It is a cyclic number.

It is not a de Polignac number, because 166541281 - 2¹³ = 166533089 is a prime.

It is a super-2 number, since 2×166541281² = 55471996554241922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166541201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83270640 + 83270641.

It is an arithmetic number, because the mean of its divisors is an integer number (83270641).

Almost surely, 2^166541281 is an apocalyptic number.

It is an amenable number.

166541281 is a deficient number, since it is larger than the sum of its proper divisors (1).

166541281 is an equidigital number, since it uses as much as digits as its factorization.

166541281 is an odious number, because the sum of its binary digits is odd.

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

The square root of 166541281 is about 12905.0874076854. The cubic root of 166541281 is about 550.1831687439.

The spelling of 166541281 in words is "one hundred sixty-six million, five hundred forty-one thousand, two hundred eighty-one".