21301221001 has 2 divisors, whose sum is σ = 21301221002. Its totient is φ = 21301221000.

The previous prime is 21301220959. The next prime is 21301221023. The reversal of 21301221001 is 10012210312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21076070976 + 225150025 = 145176^2 + 15005^2 .

It is a cyclic number.

It is not a de Polignac number, because 21301221001 - 2¹⁹ = 21300696713 is a prime.

It is a super-2 number, since 2×21301221001² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21301221101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650610500 + 10650610501.

It is an arithmetic number, because the mean of its divisors is an integer number (10650610501).

Almost surely, 2^21301221001 is an apocalyptic number.

It is an amenable number.

21301221001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21301221001 is an equidigital number, since it uses as much as digits as its factorization.

21301221001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21301221001 its reverse (10012210312), we get a palindrome (31313431313).

The spelling of 21301221001 in words is "twenty-one billion, three hundred one million, two hundred twenty-one thousand, one".