21212012023 has 2 divisors, whose sum is σ = 21212012024. Its totient is φ = 21212012022.

The previous prime is 21212011969. The next prime is 21212012033. The reversal of 21212012023 is 32021021212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21212012023 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212011988 and 21212012006.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21212012033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606006011 + 10606006012.

It is an arithmetic number, because the mean of its divisors is an integer number (10606006012).

Almost surely, 2^21212012023 is an apocalyptic number.

21212012023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212012023 is an equidigital number, since it uses as much as digits as its factorization.

21212012023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21212012023 its reverse (32021021212), we get a palindrome (53233033235).

The spelling of 21212012023 in words is "twenty-one billion, two hundred twelve million, twelve thousand, twenty-three".