21211241 has 4 divisors (see below), whose sum is σ = 21662592. Its totient is φ = 20759892.

The previous prime is 21211237. The next prime is 21211247. The reversal of 21211241 is 14211212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21211241 - 2² = 21211237 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21211247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225605 + ... + 225698.

It is an arithmetic number, because the mean of its divisors is an integer number (5415648).

Almost surely, 2^21211241 is an apocalyptic number.

It is an amenable number.

21211241 is a deficient number, since it is larger than the sum of its proper divisors (451351).

21211241 is an equidigital number, since it uses as much as digits as its factorization.

21211241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451350.

The product of its digits is 32, while the sum is 14.

The square root of 21211241 is about 4605.5663061126. The cubic root of 21211241 is about 276.8144090823.

Adding to 21211241 its reverse (14211212), we get a palindrome (35422453).

The spelling of 21211241 in words is "twenty-one million, two hundred eleven thousand, two hundred forty-one".