3943889 has 4 divisors (see below), whose sum is σ = 4018356. Its totient is φ = 3869424.

The previous prime is 3943883. The next prime is 3943921. The reversal of 3943889 is 9883493.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9883493 = 53 ⋅186481.

It can be written as a sum of positive squares in 2 ways, for example, as 2455489 + 1488400 = 1567^2 + 1220^2 .

It is not a de Polignac number, because 3943889 - 2⁴ = 3943873 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3943883) 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, 37154 + ... + 37259.

It is an arithmetic number, because the mean of its divisors is an integer number (1004589).

Almost surely, 2^3943889 is an apocalyptic number.

It is an amenable number.

3943889 is a deficient number, since it is larger than the sum of its proper divisors (74467).

3943889 is an equidigital number, since it uses as much as digits as its factorization.

3943889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74466.

The product of its digits is 186624, while the sum is 44.

The square root of 3943889 is about 1985.9227074587. The cubic root of 3943889 is about 157.9943516648.

The spelling of 3943889 in words is "three million, nine hundred forty-three thousand, eight hundred eighty-nine".