11211311021 has 2 divisors, whose sum is σ = 11211311022. Its totient is φ = 11211311020.

The previous prime is 11211310997. The next prime is 11211311053. The reversal of 11211311021 is 12011311211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8151561796 + 3059749225 = 90286^2 + 55315^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11211311021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11211310987 and 11211311005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11211311081) 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, 5605655510 + 5605655511.

It is an arithmetic number, because the mean of its divisors is an integer number (5605655511).

Almost surely, 2^11211311021 is an apocalyptic number.

It is an amenable number.

11211311021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11211311021 is an equidigital number, since it uses as much as digits as its factorization.

11211311021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 14.

Adding to 11211311021 its reverse (12011311211), we get a palindrome (23222622232).

The spelling of 11211311021 in words is "eleven billion, two hundred eleven million, three hundred eleven thousand, twenty-one".