3940781 has 8 divisors (see below), whose sum is σ = 4390680. Its totient is φ = 3511872.

The previous prime is 3940777. The next prime is 3940793. The reversal of 3940781 is 1870493.

3940781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1020100 + 2920681 = 1010^2 + 1709^2 .

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

It is not a de Polignac number, because 3940781 - 2² = 3940777 is a prime.

It is a super-2 number, since 2×3940781² = 31059509779922, 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 (3940721) 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 7 ways as a sum of consecutive naturals, for example, 4850 + ... + 5603.

It is an arithmetic number, because the mean of its divisors is an integer number (548835).

Almost surely, 2^3940781 is an apocalyptic number.

It is an amenable number.

3940781 is a deficient number, since it is larger than the sum of its proper divisors (449899).

3940781 is a wasteful number, since it uses less digits than its factorization.

3940781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10495.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 3940781 is about 1985.1400454376. The cubic root of 3940781 is about 157.9528380309.

The spelling of 3940781 in words is "three million, nine hundred forty thousand, seven hundred eighty-one".