381218329 has 2 divisors, whose sum is σ = 381218330. Its totient is φ = 381218328.

The previous prime is 381218317. The next prime is 381218333. The reversal of 381218329 is 923812183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 373378329 + 7840000 = 19323^2 + 2800^2 .

It is a cyclic number.

It is not a de Polignac number, because 381218329 - 2⁵ = 381218297 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (381218359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190609164 + 190609165.

It is an arithmetic number, because the mean of its divisors is an integer number (190609165).

Almost surely, 2^381218329 is an apocalyptic number.

It is an amenable number.

381218329 is a deficient number, since it is larger than the sum of its proper divisors (1).

381218329 is an equidigital number, since it uses as much as digits as its factorization.

381218329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 37.

The square root of 381218329 is about 19524.8131617181. The cubic root of 381218329 is about 725.0889016626.

The spelling of 381218329 in words is "three hundred eighty-one million, two hundred eighteen thousand, three hundred twenty-nine".