1161098806981 has 2 divisors, whose sum is σ = 1161098806982. Its totient is φ = 1161098806980.

The previous prime is 1161098806909. The next prime is 1161098807009. The reversal of 1161098806981 is 1896088901611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 885010562500 + 276088244481 = 940750^2 + 525441^2 .

It is a cyclic number.

It is not a de Polignac number, because 1161098806981 - 2⁷ = 1161098806853 is a prime.

It is a super-2 number, since 2×1161098806981² (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 (1161093806981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580549403490 + 580549403491.

It is an arithmetic number, because the mean of its divisors is an integer number (580549403491).

Almost surely, 2^{1161098806981} is an apocalyptic number.

It is an amenable number.

1161098806981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1161098806981 is an equidigital number, since it uses as much as digits as its factorization.

1161098806981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 58.

The spelling of 1161098806981 in words is "one trillion, one hundred sixty-one billion, ninety-eight million, eight hundred six thousand, nine hundred eighty-one".