381366191 has 2 divisors, whose sum is σ = 381366192. Its totient is φ = 381366190.

The previous prime is 381366169. The next prime is 381366199. The reversal of 381366191 is 191663183.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 381366191 - 2⁶ = 381366127 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381366199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190683095 + 190683096.

It is an arithmetic number, because the mean of its divisors is an integer number (190683096).

Almost surely, 2^381366191 is an apocalyptic number.

381366191 is a deficient number, since it is larger than the sum of its proper divisors (1).

381366191 is an equidigital number, since it uses as much as digits as its factorization.

381366191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 38.

The square root of 381366191 is about 19528.5993097303. The cubic root of 381366191 is about 725.1826355578.

The spelling of 381366191 in words is "three hundred eighty-one million, three hundred sixty-six thousand, one hundred ninety-one".