11111001001021 has 2 divisors, whose sum is σ = 11111001001022. Its totient is φ = 11111001001020.

The previous prime is 11111001001007. The next prime is 11111001001229. The reversal of 11111001001021 is 12010010011111.

11111001001021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8992261664100 + 2118739336921 = 2998710^2 + 1455589^2 .

It is a cyclic number.

It is not a de Polignac number, because 11111001001021 - 2⁷ = 11111001000893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11111001000989 and 11111001001007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11111001061021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555500500510 + 5555500500511.

It is an arithmetic number, because the mean of its divisors is an integer number (5555500500511).

Almost surely, 2^{11111001001021} is an apocalyptic number.

It is an amenable number.

11111001001021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111001001021 is an equidigital number, since it uses as much as digits as its factorization.

11111001001021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2, while the sum is 10.

Adding to 11111001001021 its reverse (12010010011111), we get a palindrome (23121011012132).

The spelling of 11111001001021 in words is "eleven trillion, one hundred eleven billion, one million, one thousand, twenty-one".