11211111112021 has 2 divisors, whose sum is σ = 11211111112022. Its totient is φ = 11211111112020.

The previous prime is 11211111111997. The next prime is 11211111112067. The reversal of 11211111112021 is 12021111111211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11075750400625 + 135360711396 = 3328025^2 + 367914^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11211111112021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11211111111986 and 11211111112004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11211111122021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5605555556010 + 5605555556011.

It is an arithmetic number, because the mean of its divisors is an integer number (5605555556011).

Almost surely, 2^{11211111112021} is an apocalyptic number.

It is an amenable number.

11211111112021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11211111112021 is an equidigital number, since it uses as much as digits as its factorization.

11211111112021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 11211111112021 its reverse (12021111111211), we get a palindrome (23232222223232).

The spelling of 11211111112021 in words is "eleven trillion, two hundred eleven billion, one hundred eleven million, one hundred twelve thousand, twenty-one".