21030244 has 12 divisors (see below), whose sum is σ = 37586304. Its totient is φ = 10291304.

The previous prime is 21030239. The next prime is 21030287. The reversal of 21030244 is 44203012.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55744 + ... + 56119.

It is an arithmetic number, because the mean of its divisors is an integer number (3132192).

Almost surely, 2^21030244 is an apocalyptic number.

It is an amenable number.

21030244 is a deficient number, since it is larger than the sum of its proper divisors (16556060).

21030244 is a wasteful number, since it uses less digits than its factorization.

21030244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111914 (or 111912 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 21030244 is about 4585.8743986289. The cubic root of 21030244 is about 276.0247999840.

Adding to 21030244 its reverse (44203012), we get a palindrome (65233256).

The spelling of 21030244 in words is "twenty-one million, thirty thousand, two hundred forty-four".