21212012010121 has 2 divisors, whose sum is σ = 21212012010122. Its totient is φ = 21212012010120.

The previous prime is 21212012010113. The next prime is 21212012010179. The reversal of 21212012010121 is 12101021021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13584273919225 + 7627738090896 = 3685685^2 + 2761836^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212012010121 - 2³ = 21212012010113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212012010095 and 21212012010104.

It is not a weakly prime, because it can be changed into another prime (21212012010521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606006005060 + 10606006005061.

It is an arithmetic number, because the mean of its divisors is an integer number (10606006005061).

Almost surely, 2^{21212012010121} is an apocalyptic number.

It is an amenable number.

21212012010121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212012010121 is an equidigital number, since it uses as much as digits as its factorization.

21212012010121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21212012010121 its reverse (12101021021212), we get a palindrome (33313033031333).

The spelling of 21212012010121 in words is "twenty-one trillion, two hundred twelve billion, twelve million, ten thousand, one hundred twenty-one".