3981399 has 4 divisors (see below), whose sum is σ = 5308536. Its totient is φ = 2654264.

The previous prime is 3981391. The next prime is 3981401. The reversal of 3981399 is 9931893.

It is a happy number.

3981399 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 3981399 - 2³ = 3981391 is a prime.

It is a super-3 number, since 3×3981399³ (a number of 21 digits) contains 333 as substring.

It is a D-number.

3981399 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 3981399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3981391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 663564 + ... + 663569.

It is an arithmetic number, because the mean of its divisors is an integer number (1327134).

Almost surely, 2^3981399 is an apocalyptic number.

3981399 is a deficient number, since it is larger than the sum of its proper divisors (1327137).

3981399 is a wasteful number, since it uses less digits than its factorization.

3981399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1327136.

The product of its digits is 52488, while the sum is 42.

The square root of 3981399 is about 1995.3443311870. The cubic root of 3981399 is about 158.4936624029.

The spelling of 3981399 in words is "three million, nine hundred eighty-one thousand, three hundred ninety-nine".