21031331110213 has 2 divisors, whose sum is σ = 21031331110214. Its totient is φ = 21031331110212.

The previous prime is 21031331110171. The next prime is 21031331110219. The reversal of 21031331110213 is 31201113313012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21018538821604 + 12792288609 = 4584598^2 + 113103^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21031331110213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21031331110219) 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, 10515665555106 + 10515665555107.

It is an arithmetic number, because the mean of its divisors is an integer number (10515665555107).

Almost surely, 2^{21031331110213} is an apocalyptic number.

It is an amenable number.

21031331110213 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031331110213 is an equidigital number, since it uses as much as digits as its factorization.

21031331110213 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 22.

Adding to 21031331110213 its reverse (31201113313012), we get a palindrome (52232444423225).

The spelling of 21031331110213 in words is "twenty-one trillion, thirty-one billion, three hundred thirty-one million, one hundred ten thousand, two hundred thirteen".