393406289 has 2 divisors, whose sum is σ = 393406290. Its totient is φ = 393406288.

The previous prime is 393406253. The next prime is 393406291. The reversal of 393406289 is 982604393.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 383376400 + 10029889 = 19580^2 + 3167^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-393406289 is a prime.

Together with 393406291, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (393406589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 196703144 + 196703145.

It is an arithmetic number, because the mean of its divisors is an integer number (196703145).

Almost surely, 2^393406289 is an apocalyptic number.

It is an amenable number.

393406289 is a deficient number, since it is larger than the sum of its proper divisors (1).

393406289 is an equidigital number, since it uses as much as digits as its factorization.

393406289 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 44.

The square root of 393406289 is about 19834.4722390085. The cubic root of 393406289 is about 732.7352746310.

The spelling of 393406289 in words is "three hundred ninety-three million, four hundred six thousand, two hundred eighty-nine".