21744202 has 4 divisors (see below), whose sum is σ = 32616306. Its totient is φ = 10872100.

The previous prime is 21744193. The next prime is 21744209. The reversal of 21744202 is 20244712.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20985561 + 758641 = 4581^2 + 871^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21744209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5436049 + ... + 5436052.

Almost surely, 2^21744202 is an apocalyptic number.

21744202 is a deficient number, since it is larger than the sum of its proper divisors (10872104).

21744202 is a wasteful number, since it uses less digits than its factorization.

21744202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10872103.

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

The square root of 21744202 is about 4663.0678742648. The cubic root of 21744202 is about 279.1137026227.

Adding to 21744202 its reverse (20244712), we get a palindrome (41988914).

The spelling of 21744202 in words is "twenty-one million, seven hundred forty-four thousand, two hundred two".