21338730 has 48 divisors (see below), whose sum is σ = 63408384. Its totient is φ = 4877280.

The previous prime is 21338717. The next prime is 21338731. The reversal of 21338730 is 3783312.

It is a junction number, because it is equal to n+sod(n) for n = 21338694 and 21338703.

It is not an unprimeable number, because it can be changed into a prime (21338731) 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, 16306 + ... + 17565.

It is an arithmetic number, because the mean of its divisors is an integer number (1321008).

Almost surely, 2^21338730 is an apocalyptic number.

21338730 is an abundant number, since it is smaller than the sum of its proper divisors (42069654).

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

21338730 is a wasteful number, since it uses less digits than its factorization.

21338730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33891 (or 33888 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 21338730 is about 4619.3863228788. The cubic root of 21338730 is about 277.3678942665.

The spelling of 21338730 in words is "twenty-one million, three hundred thirty-eight thousand, seven hundred thirty".