21530850 has 48 divisors (see below), whose sum is σ = 58255200. Its totient is φ = 5219200.

The previous prime is 21530849. The next prime is 21530867. The reversal of 21530850 is 5803512.

It is a self number, because there is not a number n which added to its sum of digits gives 21530850.

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, 4875 + ... + 8174.

It is an arithmetic number, because the mean of its divisors is an integer number (1213650).

Almost surely, 2^21530850 is an apocalyptic number.

21530850 is an abundant number, since it is smaller than the sum of its proper divisors (36724350).

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

21530850 is a wasteful number, since it uses less digits than its factorization.

21530850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13075 (or 13070 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 21530850 is about 4640.1346963208. The cubic root of 21530850 is about 278.1978216922.

The spelling of 21530850 in words is "twenty-one million, five hundred thirty thousand, eight hundred fifty".