3981281 has 4 divisors (see below), whose sum is σ = 4215492. Its totient is φ = 3747072.

The previous prime is 3981253. The next prime is 3981301. The reversal of 3981281 is 1821893.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2588881 + 1392400 = 1609^2 + 1180^2 .

It is not a de Polignac number, because 3981281 - 2⁶ = 3981217 is a prime.

It is a super-2 number, since 2×3981281² = 31701196801922, 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 (3981181) 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, 117080 + ... + 117113.

It is an arithmetic number, because the mean of its divisors is an integer number (1053873).

Almost surely, 2^3981281 is an apocalyptic number.

It is an amenable number.

3981281 is a deficient number, since it is larger than the sum of its proper divisors (234211).

3981281 is a wasteful number, since it uses less digits than its factorization.

3981281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234210.

The product of its digits is 3456, while the sum is 32.

The square root of 3981281 is about 1995.3147621365. The cubic root of 3981281 is about 158.4920965850.

It can be divided in two parts, 39812 and 81, that added together give a palindrome (39893).

The spelling of 3981281 in words is "three million, nine hundred eighty-one thousand, two hundred eighty-one".