21231222233 has 4 divisors (see below), whose sum is σ = 22864393188. Its totient is φ = 19598051280.

The previous prime is 21231222169. The next prime is 21231222263. The reversal of 21231222233 is 33222213212.

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 3630424009 + 17600798224 = 60253^2 + 132668^2 .

It is a cyclic number.

It is not a de Polignac number, because 21231222233 - 2⁶ = 21231222169 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21231222199 and 21231222208.

It is not an unprimeable number, because it can be changed into a prime (21231222263) 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, 816585458 + ... + 816585483.

It is an arithmetic number, because the mean of its divisors is an integer number (5716098297).

Almost surely, 2^21231222233 is an apocalyptic number.

It is an amenable number.

21231222233 is a deficient number, since it is larger than the sum of its proper divisors (1633170955).

21231222233 is a wasteful number, since it uses less digits than its factorization.

21231222233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1633170954.

The product of its digits is 1728, while the sum is 23.

Adding to 21231222233 its reverse (33222213212), we get a palindrome (54453435445).

The spelling of 21231222233 in words is "twenty-one billion, two hundred thirty-one million, two hundred twenty-two thousand, two hundred thirty-three".