1111111122001 has 2 divisors, whose sum is σ = 1111111122002. Its totient is φ = 1111111122000.

The previous prime is 1111111121999. The next prime is 1111111122019. The reversal of 1111111122001 is 1002211111111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 771164985600 + 339946136401 = 878160^2 + 583049^2 .

It is a cyclic number.

It is not a de Polignac number, because 1111111122001 - 2¹ = 1111111121999 is a prime.

It is a super-2 number, since 2×1111111122001² (a number of 25 digits) contains 22 as substring.

Together with 1111111121999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1111111122301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 555555561000 + 555555561001.

It is an arithmetic number, because the mean of its divisors is an integer number (555555561001).

Almost surely, 2^{1111111122001} is an apocalyptic number.

It is an amenable number.

1111111122001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1111111122001 is an equidigital number, since it uses as much as digits as its factorization.

1111111122001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 1111111122001 its reverse (1002211111111), we get a palindrome (2113322233112).

The spelling of 1111111122001 in words is "one trillion, one hundred eleven billion, one hundred eleven million, one hundred twenty-two thousand, one".