21121013103221 has 2 divisors, whose sum is σ = 21121013103222. Its totient is φ = 21121013103220.

The previous prime is 21121013103217. The next prime is 21121013103293. The reversal of 21121013103221 is 12230131012112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20596293962596 + 524719140625 = 4538314^2 + 724375^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121013103221 - 2² = 21121013103217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21121013103193 and 21121013103202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21121013133221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560506551610 + 10560506551611.

It is an arithmetic number, because the mean of its divisors is an integer number (10560506551611).

Almost surely, 2^{21121013103221} is an apocalyptic number.

It is an amenable number.

21121013103221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121013103221 is an equidigital number, since it uses as much as digits as its factorization.

21121013103221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 21121013103221 its reverse (12230131012112), we get a palindrome (33351144115333).

The spelling of 21121013103221 in words is "twenty-one trillion, one hundred twenty-one billion, thirteen million, one hundred three thousand, two hundred twenty-one".