21212102223 has 24 divisors (see below), whose sum is σ = 34937583408. Its totient is φ = 12285741312.

The previous prime is 21212102201. The next prime is 21212102237. The reversal of 21212102223 is 32220121212.

It is not a de Polignac number, because 21212102223 - 2¹³ = 21212094031 is a prime.

It is a super-3 number, since 3×21212102223³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21212102196 and 21212102205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212102243) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5330365 + ... + 5334342.

It is an arithmetic number, because the mean of its divisors is an integer number (1455732642).

Almost surely, 2^21212102223 is an apocalyptic number.

21212102223 is a deficient number, since it is larger than the sum of its proper divisors (13725481185).

21212102223 is a wasteful number, since it uses less digits than its factorization.

21212102223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10664743 (or 10664740 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21212102223 its reverse (32220121212), we get a palindrome (53432223435).

The spelling of 21212102223 in words is "twenty-one billion, two hundred twelve million, one hundred two thousand, two hundred twenty-three".