21330445 has 16 divisors (see below), whose sum is σ = 27195840. Its totient is φ = 16015104.

The previous prime is 21330443. The next prime is 21330467. The reversal of 21330445 is 54403312.

It is a cyclic number.

It is not a de Polignac number, because 21330445 - 2¹ = 21330443 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9742 + ... + 11728.

It is an arithmetic number, because the mean of its divisors is an integer number (1699740).

Almost surely, 2^21330445 is an apocalyptic number.

It is an amenable number.

21330445 is a deficient number, since it is larger than the sum of its proper divisors (5865395).

21330445 is a wasteful number, since it uses less digits than its factorization.

21330445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2124.

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 21330445 is about 4618.4894716779. The cubic root of 21330445 is about 277.3319925598.

Adding to 21330445 its reverse (54403312), we get a palindrome (75733757).

The spelling of 21330445 in words is "twenty-one million, three hundred thirty thousand, four hundred forty-five".