21828534 has 32 divisors (see below), whose sum is σ = 53733120. Its totient is φ = 5756832.

The previous prime is 21828529. The next prime is 21828551. The reversal of 21828534 is 43582812.

It is a junction number, because it is equal to n+sod(n) for n = 21828495 and 21828504.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19444 + ... + 20535.

It is an arithmetic number, because the mean of its divisors is an integer number (1679160).

Almost surely, 2^21828534 is an apocalyptic number.

21828534 is an abundant number, since it is smaller than the sum of its proper divisors (31904586).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21828534 is a wasteful number, since it uses less digits than its factorization.

21828534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40004.

The product of its digits is 15360, while the sum is 33.

The square root of 21828534 is about 4672.1016684143. The cubic root of 21828534 is about 279.4740722853.

The spelling of 21828534 in words is "twenty-one million, eight hundred twenty-eight thousand, five hundred thirty-four".