394172329 has 2 divisors, whose sum is σ = 394172330. Its totient is φ = 394172328.

The previous prime is 394172299. The next prime is 394172341. The reversal of 394172329 is 923271493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 380835225 + 13337104 = 19515^2 + 3652^2 .

It is a cyclic number.

It is not a de Polignac number, because 394172329 - 2⁵ = 394172297 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 394172291 and 394172300.

It is not a weakly prime, because it can be changed into another prime (394172399) 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, 197086164 + 197086165.

It is an arithmetic number, because the mean of its divisors is an integer number (197086165).

Almost surely, 2^394172329 is an apocalyptic number.

It is an amenable number.

394172329 is a deficient number, since it is larger than the sum of its proper divisors (1).

394172329 is an equidigital number, since it uses as much as digits as its factorization.

394172329 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81648, while the sum is 40.

The square root of 394172329 is about 19853.7736715215. The cubic root of 394172329 is about 733.2105598644.

The spelling of 394172329 in words is "three hundred ninety-four million, one hundred seventy-two thousand, three hundred twenty-nine".