21444442 has 8 divisors (see below), whose sum is σ = 32462100. Its totient is φ = 10623744.

The previous prime is 21444433. The next prime is 21444457. The reversal of 21444442 is 24444412.

It can be written as a sum of positive squares in 2 ways, for example, as 17715681 + 3728761 = 4209^2 + 1931^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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, 48967 + ... + 49402.

Almost surely, 2^21444442 is an apocalyptic number.

21444442 is a deficient number, since it is larger than the sum of its proper divisors (11017658).

21444442 is a wasteful number, since it uses less digits than its factorization.

21444442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98480.

The product of its digits is 4096, while the sum is 25.

The square root of 21444442 is about 4630.8143992175. The cubic root of 21444442 is about 277.8251665402.

Adding to 21444442 its reverse (24444412), we get a palindrome (45888854).

The spelling of 21444442 in words is "twenty-one million, four hundred forty-four thousand, four hundred forty-two".