21031003100221 has 2 divisors, whose sum is σ = 21031003100222. Its totient is φ = 21031003100220.

The previous prime is 21031003100147. The next prime is 21031003100227. The reversal of 21031003100221 is 12200130013012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20757008432196 + 273994668025 = 4555986^2 + 523445^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031003100221 - 2²³ = 21030994711613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21031003100195 and 21031003100204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21031003100227) 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, 10515501550110 + 10515501550111.

It is an arithmetic number, because the mean of its divisors is an integer number (10515501550111).

Almost surely, 2^{21031003100221} is an apocalyptic number.

It is an amenable number.

21031003100221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031003100221 is an equidigital number, since it uses as much as digits as its factorization.

21031003100221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21031003100221 its reverse (12200130013012), we get a palindrome (33231133113233).

The spelling of 21031003100221 in words is "twenty-one trillion, thirty-one billion, three million, one hundred thousand, two hundred twenty-one".