21121334233 has 4 divisors (see below), whose sum is σ = 21131257140. Its totient is φ = 21111411328.

The previous prime is 21121334209. The next prime is 21121334239. The reversal of 21121334233 is 33243312112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6429954969 + 14691379264 = 80187^2 + 121208^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121334233 - 2¹⁷ = 21121203161 is a prime.

It is a super-2 number, since 2×21121334233² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21121334198 and 21121334207.

It is not an unprimeable number, because it can be changed into a prime (21121334239) 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, 4958260 + ... + 4962517.

It is an arithmetic number, because the mean of its divisors is an integer number (5282814285).

Almost surely, 2^21121334233 is an apocalyptic number.

It is an amenable number.

21121334233 is a deficient number, since it is larger than the sum of its proper divisors (9922907).

21121334233 is an equidigital number, since it uses as much as digits as its factorization.

21121334233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9922906.

The product of its digits is 2592, while the sum is 25.

Adding to 21121334233 its reverse (33243312112), we get a palindrome (54364646345).

The spelling of 21121334233 in words is "twenty-one billion, one hundred twenty-one million, three hundred thirty-four thousand, two hundred thirty-three".