21221112331 has 4 divisors (see below), whose sum is σ = 22338013000. Its totient is φ = 20104211664.

The previous prime is 21221112287. The next prime is 21221112361. The reversal of 21221112331 is 13321112212.

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

It is a cyclic number.

It is not a de Polignac number, because 21221112331 - 2¹⁹ = 21220588043 is a prime.

It is a super-2 number, since 2×21221112331² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 1116900649 = 21221112331 / (2 + 1 + 2 + 2 + 1 + 1 + 1 + 2 + 3 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221112299 and 21221112308.

It is not an unprimeable number, because it can be changed into a prime (21221112361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 558450306 + ... + 558450343.

It is an arithmetic number, because the mean of its divisors is an integer number (5584503250).

Almost surely, 2^21221112331 is an apocalyptic number.

21221112331 is a deficient number, since it is larger than the sum of its proper divisors (1116900669).

21221112331 is a wasteful number, since it uses less digits than its factorization.

21221112331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1116900668.

The product of its digits is 144, while the sum is 19.

Adding to 21221112331 its reverse (13321112212), we get a palindrome (34542224543).

The spelling of 21221112331 in words is "twenty-one billion, two hundred twenty-one million, one hundred twelve thousand, three hundred thirty-one".