21840326 has 16 divisors (see below), whose sum is σ = 33450144. Its totient is φ = 10692864.

The previous prime is 21840319. The next prime is 21840361. The reversal of 21840326 is 62304812.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21840295 and 21840304.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 19436 + ... + 20528.

It is an arithmetic number, because the mean of its divisors is an integer number (2090634).

Almost surely, 2^21840326 is an apocalyptic number.

21840326 is a deficient number, since it is larger than the sum of its proper divisors (11609818).

21840326 is a wasteful number, since it uses less digits than its factorization.

21840326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1295.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 21840326 is about 4673.3634568692. The cubic root of 21840326 is about 279.5243881548.

The spelling of 21840326 in words is "twenty-one million, eight hundred forty thousand, three hundred twenty-six".