21730112 has 28 divisors (see below), whose sum is σ = 43318176. Its totient is φ = 10815360.

The previous prime is 21730109. The next prime is 21730133. The reversal of 21730112 is 21103712.

It is a zygodrome in base 3.

It is a congruent number.

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, 16187 + ... + 17477.

Almost surely, 2^21730112 is an apocalyptic number.

It is an amenable number.

21730112 is a deficient number, since it is larger than the sum of its proper divisors (21588064).

21730112 is a wasteful number, since it uses less digits than its factorization.

21730112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1566 (or 1556 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 21730112 is about 4661.5568214922. The cubic root of 21730112 is about 279.0534020756.

Adding to 21730112 its reverse (21103712), we get a palindrome (42833824).

The spelling of 21730112 in words is "twenty-one million, seven hundred thirty thousand, one hundred twelve".