3997391 has 8 divisors (see below), whose sum is σ = 4278000. Its totient is φ = 3723840.

The previous prime is 3997381. The next prime is 3997403. The reversal of 3997391 is 1937993.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3997391 - 2¹⁸ = 3735247 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 (3997361) 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 in 7 ways as a sum of consecutive naturals, for example, 566 + ... + 2883.

It is an arithmetic number, because the mean of its divisors is an integer number (534750).

Almost surely, 2^3997391 is an apocalyptic number.

3997391 is a deficient number, since it is larger than the sum of its proper divisors (280609).

3997391 is a wasteful number, since it uses less digits than its factorization.

3997391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3529.

The product of its digits is 45927, while the sum is 41.

The square root of 3997391 is about 1999.3476436078. The cubic root of 3997391 is about 158.7055849459.

The spelling of 3997391 in words is "three million, nine hundred ninety-seven thousand, three hundred ninety-one".