3943999 has 2 divisors, whose sum is σ = 3944000. Its totient is φ = 3943998.

The previous prime is 3943993. The next prime is 3944009. The reversal of 3943999 is 9993493.

It is a weak prime.

It is an emirp because it is prime and its reverse (9993493) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3943999 - 2⁵ = 3943967 is a prime.

It is a super-2 number, since 2×3943999² = 31110256224002, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3943993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1971999 + 1972000.

It is an arithmetic number, because the mean of its divisors is an integer number (1972000).

Almost surely, 2^3943999 is an apocalyptic number.

3943999 is a deficient number, since it is larger than the sum of its proper divisors (1).

3943999 is an equidigital number, since it uses as much as digits as its factorization.

3943999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 236196, while the sum is 46.

The square root of 3943999 is about 1985.9504022004. The cubic root of 3943999 is about 157.9958205378.

The spelling of 3943999 in words is "three million, nine hundred forty-three thousand, nine hundred ninety-nine".