3991481 has 8 divisors (see below), whose sum is σ = 4551624. Its totient is φ = 3467520.

The previous prime is 3991469. The next prime is 3991511. The reversal of 3991481 is 1841993.

It can be written as a sum of positive squares in 4 ways, for example, as 960400 + 3031081 = 980^2 + 1741^2 .

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 3991481 - 2¹⁸ = 3729337 is a prime.

It is a super-2 number, since 2×3991481² = 31863841146722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3991441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8810 + ... + 9251.

It is an arithmetic number, because the mean of its divisors is an integer number (568953).

Almost surely, 2^3991481 is an apocalyptic number.

It is an amenable number.

3991481 is a deficient number, since it is larger than the sum of its proper divisors (560143).

3991481 is a wasteful number, since it uses less digits than its factorization.

3991481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18091.

The product of its digits is 7776, while the sum is 35.

The square root of 3991481 is about 1997.8691148321. The cubic root of 3991481 is about 158.6273328536.

The spelling of 3991481 in words is "three million, nine hundred ninety-one thousand, four hundred eighty-one".