11212011101521 has 2 divisors, whose sum is σ = 11212011101522. Its totient is φ = 11212011101520.

The previous prime is 11212011101519. The next prime is 11212011101537. The reversal of 11212011101521 is 12510111021211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6732286462225 + 4479724639296 = 2594665^2 + 2116536^2 .

It is a cyclic number.

It is not a de Polignac number, because 11212011101521 - 2¹ = 11212011101519 is a prime.

Together with 11212011101519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11212011101591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5606005550760 + 5606005550761.

It is an arithmetic number, because the mean of its divisors is an integer number (5606005550761).

Almost surely, 2^{11212011101521} is an apocalyptic number.

It is an amenable number.

11212011101521 is a deficient number, since it is larger than the sum of its proper divisors (1).

11212011101521 is an equidigital number, since it uses as much as digits as its factorization.

11212011101521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40, while the sum is 19.

Adding to 11212011101521 its reverse (12510111021211), we get a palindrome (23722122122732).

The spelling of 11212011101521 in words is "eleven trillion, two hundred twelve billion, eleven million, one hundred one thousand, five hundred twenty-one".