21111313213 has 2 divisors, whose sum is σ = 21111313214. Its totient is φ = 21111313212.

The previous prime is 21111313211. The next prime is 21111313229. The reversal of 21111313213 is 31231311112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14028744249 + 7082568964 = 118443^2 + 84158^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111313213 - 2¹ = 21111313211 is a prime.

Together with 21111313211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111313211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555656606 + 10555656607.

It is an arithmetic number, because the mean of its divisors is an integer number (10555656607).

Almost surely, 2^21111313213 is an apocalyptic number.

It is an amenable number.

21111313213 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111313213 is an equidigital number, since it uses as much as digits as its factorization.

21111313213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108, while the sum is 19.

Adding to 21111313213 its reverse (31231311112), we get a palindrome (52342624325).

The spelling of 21111313213 in words is "twenty-one billion, one hundred eleven million, three hundred thirteen thousand, two hundred thirteen".