1001111212081 has 2 divisors, whose sum is σ = 1001111212082. Its totient is φ = 1001111212080.

The previous prime is 1001111212069. The next prime is 1001111212103. The reversal of 1001111212081 is 1802121111001.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 701071290000 + 300039922081 = 837300^2 + 547759^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001111212081 - 2³⁵ = 966751473713 is a prime.

It is a super-2 number, since 2×1001111212081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1001111212021) 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, 500555606040 + 500555606041.

It is an arithmetic number, because the mean of its divisors is an integer number (500555606041).

Almost surely, 2^{1001111212081} is an apocalyptic number.

It is an amenable number.

1001111212081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001111212081 is an equidigital number, since it uses as much as digits as its factorization.

1001111212081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 1001111212081 its reverse (1802121111001), we get a palindrome (2803232323082).

The spelling of 1001111212081 in words is "one trillion, one billion, one hundred eleven million, two hundred twelve thousand, eighty-one".