21444330 has 32 divisors (see below), whose sum is σ = 52441344. Its totient is φ = 5610176.

The previous prime is 21444323. The next prime is 21444341. The reversal of 21444330 is 3344412.

It is a junction number, because it is equal to n+sod(n) for n = 21444297 and 21444306.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5154 + ... + 8333.

It is an arithmetic number, because the mean of its divisors is an integer number (1638792).

Almost surely, 2^21444330 is an apocalyptic number.

21444330 is an abundant number, since it is smaller than the sum of its proper divisors (30997014).

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

21444330 is a wasteful number, since it uses less digits than its factorization.

21444330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13550.

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 21444330 is about 4630.8023062964. The cubic root of 21444330 is about 277.8246828644.

Adding to 21444330 its reverse (3344412), we get a palindrome (24788742).

It can be divided in two parts, 214 and 44330, that added together give a palindrome (44544).

The spelling of 21444330 in words is "twenty-one million, four hundred forty-four thousand, three hundred thirty".