393922391 has 4 divisors (see below), whose sum is σ = 394379712. Its totient is φ = 393465072.

The previous prime is 393922349. The next prime is 393922393. The reversal of 393922391 is 193229393.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-393922391 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 (393922393) 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, 227366 + ... + 229091.

It is an arithmetic number, because the mean of its divisors is an integer number (98594928).

Almost surely, 2^393922391 is an apocalyptic number.

393922391 is a deficient number, since it is larger than the sum of its proper divisors (457321).

393922391 is an equidigital number, since it uses as much as digits as its factorization.

393922391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457320.

The product of its digits is 78732, while the sum is 41.

The square root of 393922391 is about 19847.4782025324. The cubic root of 393922391 is about 733.0555549639.

The spelling of 393922391 in words is "three hundred ninety-three million, nine hundred twenty-two thousand, three hundred ninety-one".