21212012219 has 2 divisors, whose sum is σ = 21212012220. Its totient is φ = 21212012218.

The previous prime is 21212012149. The next prime is 21212012231. The reversal of 21212012219 is 91221021212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21212012219 is a prime.

It is a super-2 number, since 2×21212012219² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21212012194 and 21212012203.

It is not a weakly prime, because it can be changed into another prime (21212012249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606006109 + 10606006110.

It is an arithmetic number, because the mean of its divisors is an integer number (10606006110).

Almost surely, 2^21212012219 is an apocalyptic number.

21212012219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212012219 is an equidigital number, since it uses as much as digits as its factorization.

21212012219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 23.

The spelling of 21212012219 in words is "twenty-one billion, two hundred twelve million, twelve thousand, two hundred nineteen".