3947838 has 8 divisors (see below), whose sum is σ = 7895688. Its totient is φ = 1315944.

The previous prime is 3947833. The next prime is 3947843. The reversal of 3947838 is 8387493.

It is an interprime number because it is at equal distance from previous prime (3947833) and next prime (3947843).

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

3947838 is an admirable number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 3947838.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3947831) 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, 328981 + ... + 328992.

It is an arithmetic number, because the mean of its divisors is an integer number (986961).

Almost surely, 2^3947838 is an apocalyptic number.

3947838 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3947838 is a wasteful number, since it uses less digits than its factorization.

3947838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657978.

The product of its digits is 145152, while the sum is 42.

The square root of 3947838 is about 1986.9167068602. The cubic root of 3947838 is about 158.0470671078.

The spelling of 3947838 in words is "three million, nine hundred forty-seven thousand, eight hundred thirty-eight".