21069324 has 72 divisors (see below), whose sum is σ = 57002400. Its totient is φ = 6538752.

The previous prime is 21069319. The next prime is 21069343. The reversal of 21069324 is 42396012.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 105777 + ... + 105975.

It is an arithmetic number, because the mean of its divisors is an integer number (791700).

Almost surely, 2^21069324 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21069324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28501200).

21069324 is an abundant number, since it is smaller than the sum of its proper divisors (35933076).

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

21069324 is a wasteful number, since it uses less digits than its factorization.

21069324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399 (or 394 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 21069324 is about 4590.1333313968. The cubic root of 21069324 is about 276.1956709496.

The spelling of 21069324 in words is "twenty-one million, sixty-nine thousand, three hundred twenty-four".