21212021121229 has 2 divisors, whose sum is σ = 21212021121230. Its totient is φ = 21212021121228.

The previous prime is 21212021121211. The next prime is 21212021121283. The reversal of 21212021121229 is 92212112021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17365539171204 + 3846481950025 = 4167198^2 + 1961245^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212021121229 - 2²⁵ = 21211987566797 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212021121197 and 21212021121206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21212021128229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606010560614 + 10606010560615.

It is an arithmetic number, because the mean of its divisors is an integer number (10606010560615).

Almost surely, 2^{21212021121229} is an apocalyptic number.

It is an amenable number.

21212021121229 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212021121229 is an equidigital number, since it uses as much as digits as its factorization.

21212021121229 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 28.

The spelling of 21212021121229 in words is "twenty-one trillion, two hundred twelve billion, twenty-one million, one hundred twenty-one thousand, two hundred twenty-nine".