22278399 has 24 divisors (see below), whose sum is σ = 35169456. Its totient is φ = 12460800.

The previous prime is 22278383. The next prime is 22278407. The reversal of 22278399 is 99387222.

It is a Cunningham number, because it is equal to 4720²-1.

It is not a de Polignac number, because 22278399 - 2⁴ = 22278383 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 22278399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22278379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2359 + ... + 7079.

It is an arithmetic number, because the mean of its divisors is an integer number (1465394).

Almost surely, 2^22278399 is an apocalyptic number.

22278399 is a deficient number, since it is larger than the sum of its proper divisors (12891057).

22278399 is a wasteful number, since it uses less digits than its factorization.

22278399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4759 (or 4748 counting only the distinct ones).

The product of its digits is 108864, while the sum is 42.

The square root of 22278399 is about 4719.9998940678. Note that the first 3 decimals coincide. The cubic root of 22278399 is about 281.3809290644.

The spelling of 22278399 in words is "twenty-two million, two hundred seventy-eight thousand, three hundred ninety-nine".