21241221331 has 16 divisors (see below), whose sum is σ = 23807714400. Its totient is φ = 18781044480.

The previous prime is 21241221293. The next prime is 21241221343. The reversal of 21241221331 is 13312214212.

It is not a de Polignac number, because 21241221331 - 2²⁵ = 21207666899 is a prime.

It is a super-2 number, since 2×21241221331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21241221371) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1232385 + ... + 1249501.

It is an arithmetic number, because the mean of its divisors is an integer number (1487982150).

Almost surely, 2^21241221331 is an apocalyptic number.

21241221331 is a deficient number, since it is larger than the sum of its proper divisors (2566493069).

21241221331 is a wasteful number, since it uses less digits than its factorization.

21241221331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20214.

The product of its digits is 576, while the sum is 22.

Adding to 21241221331 its reverse (13312214212), we get a palindrome (34553435543).

The spelling of 21241221331 in words is "twenty-one billion, two hundred forty-one million, two hundred twenty-one thousand, three hundred thirty-one".