21198931213 has 2 divisors, whose sum is σ = 21198931214. Its totient is φ = 21198931212.

The previous prime is 21198931153. The next prime is 21198931261. The reversal of 21198931213 is 31213989112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10766760169 + 10432171044 = 103763^2 + 102138^2 .

It is a cyclic number.

It is not a de Polignac number, because 21198931213 - 2¹³ = 21198923021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21198931513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10599465606 + 10599465607.

It is an arithmetic number, because the mean of its divisors is an integer number (10599465607).

Almost surely, 2^21198931213 is an apocalyptic number.

It is an amenable number.

21198931213 is a deficient number, since it is larger than the sum of its proper divisors (1).

21198931213 is an equidigital number, since it uses as much as digits as its factorization.

21198931213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 40.

The spelling of 21198931213 in words is "twenty-one billion, one hundred ninety-eight million, nine hundred thirty-one thousand, two hundred thirteen".