181666379 has 2 divisors, whose sum is σ = 181666380. Its totient is φ = 181666378.

The previous prime is 181666363. The next prime is 181666393. The reversal of 181666379 is 973666181.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 181666379 - 2⁴ = 181666363 is a prime.

It is not a weakly prime, because it can be changed into another prime (181666319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90833189 + 90833190.

It is an arithmetic number, because the mean of its divisors is an integer number (90833190).

Almost surely, 2^181666379 is an apocalyptic number.

181666379 is a deficient number, since it is larger than the sum of its proper divisors (1).

181666379 is an equidigital number, since it uses as much as digits as its factorization.

181666379 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 47.

The square root of 181666379 is about 13478.3670746868. The cubic root of 181666379 is about 566.3586266205.

The spelling of 181666379 in words is "one hundred eighty-one million, six hundred sixty-six thousand, three hundred seventy-nine".