21212102237 has 2 divisors, whose sum is σ = 21212102238. Its totient is φ = 21212102236.

The previous prime is 21212102201. The next prime is 21212102243. The reversal of 21212102237 is 73220121212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13546399321 + 7665702916 = 116389^2 + 87554^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212102237 - 2¹⁶ = 21212036701 is a prime.

It is a super-3 number, since 3×21212102237³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21212102267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606051118 + 10606051119.

It is an arithmetic number, because the mean of its divisors is an integer number (10606051119).

Almost surely, 2^21212102237 is an apocalyptic number.

It is an amenable number.

21212102237 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212102237 is an equidigital number, since it uses as much as digits as its factorization.

21212102237 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 23.

Adding to 21212102237 its reverse (73220121212), we get a palindrome (94432223449).

The spelling of 21212102237 in words is "twenty-one billion, two hundred twelve million, one hundred two thousand, two hundred thirty-seven".