22128813 has 24 divisors (see below), whose sum is σ = 36736128. Its totient is φ = 12573792.

The previous prime is 22128811. The next prime is 22128839. The reversal of 22128813 is 31882122.

It is not a de Polignac number, because 22128813 - 2¹ = 22128811 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22128811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11520 + ... + 13302.

It is an arithmetic number, because the mean of its divisors is an integer number (1530672).

Almost surely, 2^22128813 is an apocalyptic number.

It is an amenable number.

22128813 is a deficient number, since it is larger than the sum of its proper divisors (14607315).

22128813 is a wasteful number, since it uses less digits than its factorization.

22128813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1993 (or 1990 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 22128813 is about 4704.1272304222. The cubic root of 22128813 is about 280.7497465893.

It can be divided in two parts, 2212 and 8813, that added together give a square (11025 = 105²).

The spelling of 22128813 in words is "twenty-two million, one hundred twenty-eight thousand, eight hundred thirteen".