166558331 has 2 divisors, whose sum is σ = 166558332. Its totient is φ = 166558330.

The previous prime is 166558321. The next prime is 166558391. The reversal of 166558331 is 133855661.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166558331 is a prime.

It is a super-3 number, since 3×166558331³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (166558321) 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, 83279165 + 83279166.

It is an arithmetic number, because the mean of its divisors is an integer number (83279166).

Almost surely, 2^166558331 is an apocalyptic number.

166558331 is a deficient number, since it is larger than the sum of its proper divisors (1).

166558331 is an equidigital number, since it uses as much as digits as its factorization.

166558331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64800, while the sum is 38.

The square root of 166558331 is about 12905.7479829725. The cubic root of 166558331 is about 550.2019434742.

The spelling of 166558331 in words is "one hundred sixty-six million, five hundred fifty-eight thousand, three hundred thirty-one".