1011001109981 has 2 divisors, whose sum is σ = 1011001109982. Its totient is φ = 1011001109980.

The previous prime is 1011001109957. The next prime is 1011001110017. The reversal of 1011001109981 is 1899011001101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 739316227225 + 271684882756 = 859835^2 + 521234^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011001109981 - 2³⁰ = 1009927368157 is a prime.

It is a super-2 number, since 2×1011001109981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1011001109081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505500554990 + 505500554991.

It is an arithmetic number, because the mean of its divisors is an integer number (505500554991).

Almost surely, 2^{1011001109981} is an apocalyptic number.

It is an amenable number.

1011001109981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011001109981 is an equidigital number, since it uses as much as digits as its factorization.

1011001109981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 32.

The spelling of 1011001109981 in words is "one trillion, eleven billion, one million, one hundred nine thousand, nine hundred eighty-one".