3945781 has 8 divisors (see below), whose sum is σ = 4540544. Its totient is φ = 3358800.

The previous prime is 3945761. The next prime is 3945803. The reversal of 3945781 is 1875493.

3945781 is digitally balanced in base 8, because in such base it contains all the possibile digits an equal number of times.

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 3945781 - 2¹⁷ = 3814709 is a prime.

It is a super-2 number, since 2×3945781² = 31138375399922, which contains 22 as substring.

It is a Duffinian number.

3945781 is strictly pandigital in base 8.

It is a self number, because there is not a number n which added to its sum of digits gives 3945781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3945701) 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, 810 + ... + 2923.

It is an arithmetic number, because the mean of its divisors is an integer number (567568).

Almost surely, 2^3945781 is an apocalyptic number.

It is an amenable number.

3945781 is a deficient number, since it is larger than the sum of its proper divisors (594763).

3945781 is a wasteful number, since it uses less digits than its factorization.

3945781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3891.

The product of its digits is 30240, while the sum is 37.

The square root of 3945781 is about 1986.3990032217. The cubic root of 3945781 is about 158.0196124776.

The spelling of 3945781 in words is "three million, nine hundred forty-five thousand, seven hundred eighty-one".