3891943 has 4 divisors (see below), whose sum is σ = 4245768. Its totient is φ = 3538120.

The previous prime is 3891917. The next prime is 3891971. The reversal of 3891943 is 3491983.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3491983 = 11 ⋅317453.

It is a cyclic number.

It is not a de Polignac number, because 3891943 - 2⁹ = 3891431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3891913) 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, 176896 + ... + 176917.

It is an arithmetic number, because the mean of its divisors is an integer number (1061442).

Almost surely, 2^3891943 is an apocalyptic number.

3891943 is a deficient number, since it is larger than the sum of its proper divisors (353825).

3891943 is a wasteful number, since it uses less digits than its factorization.

3891943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353824.

The product of its digits is 23328, while the sum is 37.

The square root of 3891943 is about 1972.8008008920. The cubic root of 3891943 is about 157.2976219860.

It can be divided in two parts, 389 and 1943, that added together give a palindrome (2332).

The spelling of 3891943 in words is "three million, eight hundred ninety-one thousand, nine hundred forty-three".