21549330 has 48 divisors (see below), whose sum is σ = 61124544. Its totient is φ = 5223840.

The previous prime is 21549301. The next prime is 21549389. The reversal of 21549330 is 3394512.

It is a junction number, because it is equal to n+sod(n) for n = 21549294 and 21549303.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9894 + ... + 11873.

It is an arithmetic number, because the mean of its divisors is an integer number (1273428).

Almost surely, 2^21549330 is an apocalyptic number.

21549330 is an abundant number, since it is smaller than the sum of its proper divisors (39575214).

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

21549330 is a wasteful number, since it uses less digits than its factorization.

21549330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21791 (or 21788 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 21549330 is about 4642.1255907181. The cubic root of 21549330 is about 278.2773916360.

The spelling of 21549330 in words is "twenty-one million, five hundred forty-nine thousand, three hundred thirty".