22399 has 4 divisors (see below), whose sum is σ = 24136. Its totient is φ = 20664.

The previous prime is 22397. The next prime is 22409. The reversal of 22399 is 99322.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 22399 - 2¹ = 22397 is a prime.

It is a Duffinian number.

22399 is a lucky number.

It is a plaindrome in base 10 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22391) 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, 849 + ... + 874.

It is an arithmetic number, because the mean of its divisors is an integer number (6034).

2²²³⁹⁹ is an apocalyptic number.

22399 is a deficient number, since it is larger than the sum of its proper divisors (1737).

22399 is a wasteful number, since it uses less digits than its factorization.

22399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1736.

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

The square root of 22399 is about 149.6629546681. The cubic root of 22399 is about 28.1887754399.

It can be divided in two parts, 22 and 399, that multiplied together give a palindrome (8778).

The spelling of 22399 in words is "twenty-two thousand, three hundred ninety-nine".