1001111121001 has 2 divisors, whose sum is σ = 1001111121002. Its totient is φ = 1001111121000.

The previous prime is 1001111120987. The next prime is 1001111121013. The reversal of 1001111121001 is 1001211111001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 946038296025 + 55072824976 = 972645^2 + 234676^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001111121001 - 2⁵ = 1001111120969 is a prime.

It is not a weakly prime, because it can be changed into another prime (1001111121071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500555560500 + 500555560501.

It is an arithmetic number, because the mean of its divisors is an integer number (500555560501).

Almost surely, 2^{1001111121001} is an apocalyptic number.

It is an amenable number.

1001111121001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001111121001 is an equidigital number, since it uses as much as digits as its factorization.

1001111121001 is an odious number, because the sum of its binary digits is odd.

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

Adding to 1001111121001 its reverse (1001211111001), we get a palindrome (2002322232002).

The spelling of 1001111121001 in words is "one trillion, one billion, one hundred eleven million, one hundred twenty-one thousand, one".