21267211 has 8 divisors (see below), whose sum is σ = 24334560. Its totient is φ = 18207168.

The previous prime is 21267161. The next prime is 21267227. The reversal of 21267211 is 11276212.

It is a happy number.

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

It is not a de Polignac number, because 21267211 - 2⁷ = 21267083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21267011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7845 + ... + 10201.

It is an arithmetic number, because the mean of its divisors is an integer number (3041820).

Almost surely, 2^21267211 is an apocalyptic number.

21267211 is a deficient number, since it is larger than the sum of its proper divisors (3067349).

21267211 is a wasteful number, since it uses less digits than its factorization.

21267211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3653.

The product of its digits is 336, while the sum is 22.

The square root of 21267211 is about 4611.6386458611. The cubic root of 21267211 is about 277.0576715275.

Subtracting from 21267211 its reverse (11276212), we obtain a palindrome (9990999).

The spelling of 21267211 in words is "twenty-one million, two hundred sixty-seven thousand, two hundred eleven".