166438361 has 2 divisors, whose sum is σ = 166438362. Its totient is φ = 166438360.

The previous prime is 166438301. The next prime is 166438367. The reversal of 166438361 is 163834661.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161290000 + 5148361 = 12700^2 + 2269^2 .

It is a cyclic number.

It is not a de Polignac number, because 166438361 - 2⁶ = 166438297 is a prime.

It is not a weakly prime, because it can be changed into another prime (166438367) 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, 83219180 + 83219181.

It is an arithmetic number, because the mean of its divisors is an integer number (83219181).

Almost surely, 2^166438361 is an apocalyptic number.

It is an amenable number.

166438361 is a deficient number, since it is larger than the sum of its proper divisors (1).

166438361 is an equidigital number, since it uses as much as digits as its factorization.

166438361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 38.

The square root of 166438361 is about 12901.0992167334. The cubic root of 166438361 is about 550.0698104225.

The spelling of 166438361 in words is "one hundred sixty-six million, four hundred thirty-eight thousand, three hundred sixty-one".