21030221212321 has 2 divisors, whose sum is σ = 21030221212322. Its totient is φ = 21030221212320.

The previous prime is 21030221212309. The next prime is 21030221212349. The reversal of 21030221212321 is 12321212203012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21027140407296 + 3080805025 = 4585536^2 + 55505^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030221212321 - 2²³ = 21030212823713 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21030221212292 and 21030221212301.

It is not a weakly prime, because it can be changed into another prime (21030224212321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515110606160 + 10515110606161.

It is an arithmetic number, because the mean of its divisors is an integer number (10515110606161).

Almost surely, 2^{21030221212321} is an apocalyptic number.

It is an amenable number.

21030221212321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030221212321 is an equidigital number, since it uses as much as digits as its factorization.

21030221212321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 22.

Adding to 21030221212321 its reverse (12321212203012), we get a palindrome (33351433415333).

The spelling of 21030221212321 in words is "twenty-one trillion, thirty billion, two hundred twenty-one million, two hundred twelve thousand, three hundred twenty-one".