21828111 has 8 divisors (see below), whose sum is σ = 29251200. Its totient is φ = 14478552.

The previous prime is 21828101. The next prime is 21828151. The reversal of 21828111 is 11182812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21828111 - 2¹⁸ = 21565967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21828101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17685 + ... + 18878.

It is an arithmetic number, because the mean of its divisors is an integer number (3656400).

Almost surely, 2^21828111 is an apocalyptic number.

21828111 is a deficient number, since it is larger than the sum of its proper divisors (7423089).

21828111 is a wasteful number, since it uses less digits than its factorization.

21828111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36765.

The product of its digits is 256, while the sum is 24.

The square root of 21828111 is about 4672.0563994883. The cubic root of 21828111 is about 279.4722670290.

It can be divided in two parts, 2182811 and 1, that added together give a palindrome (2182812).

The spelling of 21828111 in words is "twenty-one million, eight hundred twenty-eight thousand, one hundred eleven".