21744022 has 16 divisors (see below), whose sum is σ = 33565392. Its totient is φ = 10558080.

The previous prime is 21744011. The next prime is 21744031. The reversal of 21744022 is 22044712.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21743984 and 21744002.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22738 + ... + 23674.

It is an arithmetic number, because the mean of its divisors is an integer number (2097837).

Almost surely, 2^21744022 is an apocalyptic number.

21744022 is a deficient number, since it is larger than the sum of its proper divisors (11821370).

21744022 is a wasteful number, since it uses less digits than its factorization.

21744022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263.

The product of its (nonzero) digits is 896, while the sum is 22.

The square root of 21744022 is about 4663.0485736265. The cubic root of 21744022 is about 279.1129324464.

Adding to 21744022 its reverse (22044712), we get a palindrome (43788734).

The spelling of 21744022 in words is "twenty-one million, seven hundred forty-four thousand, twenty-two".