3993391 has 4 divisors (see below), whose sum is σ = 4068792. Its totient is φ = 3917992.

The previous prime is 3993377. The next prime is 3993397. The reversal of 3993391 is 1933993.

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 3993391 - 2⁷ = 3993263 is a prime.

It is a Duffinian number.

3993391 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 3993391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3993397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37621 + ... + 37726.

It is an arithmetic number, because the mean of its divisors is an integer number (1017198).

Almost surely, 2^3993391 is an apocalyptic number.

3993391 is a deficient number, since it is larger than the sum of its proper divisors (75401).

3993391 is an equidigital number, since it uses as much as digits as its factorization.

3993391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75400.

The product of its digits is 19683, while the sum is 37.

The square root of 3993391 is about 1998.3470669531. The cubic root of 3993391 is about 158.6526308897.

The spelling of 3993391 in words is "three million, nine hundred ninety-three thousand, three hundred ninety-one".