3981919 has 4 divisors (see below), whose sum is σ = 4110400. Its totient is φ = 3853440.

The previous prime is 3981917. The next prime is 3981937. The reversal of 3981919 is 9191893.

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 3981919 - 2¹ = 3981917 is a prime.

It is a super-2 number, since 2×3981919² = 31711357845122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3981911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64194 + ... + 64255.

It is an arithmetic number, because the mean of its divisors is an integer number (1027600).

Almost surely, 2^3981919 is an apocalyptic number.

3981919 is a deficient number, since it is larger than the sum of its proper divisors (128481).

3981919 is a wasteful number, since it uses less digits than its factorization.

3981919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128480.

The product of its digits is 17496, while the sum is 40.

The square root of 3981919 is about 1995.4746302572. The cubic root of 3981919 is about 158.5005622486.

It can be divided in two parts, 3981 and 919, that added together give a square (4900 = 70²).

The spelling of 3981919 in words is "three million, nine hundred eighty-one thousand, nine hundred nineteen".