4399 has 4 divisors (see below), whose sum is σ = 4536. Its totient is φ = 4264.

The previous prime is 4397. The next prime is 4409. The reversal of 4399 is 9934.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9934 = 2 ⋅4967.

It is a cyclic number.

It is not a de Polignac number, because 4399 - 2¹ = 4397 is a prime.

It is a Duffinian number.

4399 is a modest number, since divided by 99 gives 43 as remainder.

4399 is a lucky number.

It is a plaindrome in base 11, base 12 and base 16.

It is a nialpdrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12 + ... + 94.

It is an arithmetic number, because the mean of its divisors is an integer number (1134).

2⁴³⁹⁹ is an apocalyptic number.

4399 is a deficient number, since it is larger than the sum of its proper divisors (137).

4399 is an equidigital number, since it uses as much as digits as its factorization.

4399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136.

The product of its digits is 972, while the sum is 25.

The square root of 4399 is about 66.3249575952. The cubic root of 4399 is about 16.3851839221.

It can be divided in two parts, 4 and 399, that multiplied together give a triangular number (1596 = T₅₆).

The spelling of 4399 in words is "four thousand, three hundred ninety-nine".