393694391 has 4 divisors (see below), whose sum is σ = 393763032. Its totient is φ = 393625752.

The previous prime is 393694387. The next prime is 393694397. The reversal of 393694391 is 193496393.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 393694391 - 2² = 393694387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (393694397) 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 in 3 ways as a sum of consecutive naturals, for example, 24845 + ... + 37478.

It is an arithmetic number, because the mean of its divisors is an integer number (98440758).

Almost surely, 2^393694391 is an apocalyptic number.

393694391 is a deficient number, since it is larger than the sum of its proper divisors (68641).

393694391 is an equidigital number, since it uses as much as digits as its factorization.

393694391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68640.

The product of its digits is 472392, while the sum is 47.

The square root of 393694391 is about 19841.7335684158. The cubic root of 393694391 is about 732.9140982314.

The spelling of 393694391 in words is "three hundred ninety-three million, six hundred ninety-four thousand, three hundred ninety-one".