21243211 has 8 divisors (see below), whose sum is σ = 23298048. Its totient is φ = 19209000.

The previous prime is 21243193. The next prime is 21243227. The reversal of 21243211 is 11234212.

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

It is a cyclic number.

It is not a de Polignac number, because 21243211 - 2¹¹ = 21241163 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21243011) 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, 2955 + ... + 7156.

It is an arithmetic number, because the mean of its divisors is an integer number (2912256).

Almost surely, 2^21243211 is an apocalyptic number.

21243211 is a deficient number, since it is larger than the sum of its proper divisors (2054837).

21243211 is a wasteful number, since it uses less digits than its factorization.

21243211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10313.

The product of its digits is 96, while the sum is 16.

The square root of 21243211 is about 4609.0357993836. The cubic root of 21243211 is about 276.9534126450.

Adding to 21243211 its reverse (11234212), we get a palindrome (32477423).

It can be divided in two parts, 2124 and 3211, that added together give a palindrome (5335).

The spelling of 21243211 in words is "twenty-one million, two hundred forty-three thousand, two hundred eleven".