1231140109981 has 2 divisors, whose sum is σ = 1231140109982. Its totient is φ = 1231140109980.

The previous prime is 1231140109943. The next prime is 1231140110071. The reversal of 1231140109981 is 1899010411321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 786396504100 + 444743605881 = 886790^2 + 666891^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231140109981 - 2¹⁵ = 1231140077213 is a prime.

It is a super-2 number, since 2×1231140109981² (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 (1231140101981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615570054990 + 615570054991.

It is an arithmetic number, because the mean of its divisors is an integer number (615570054991).

Almost surely, 2^{1231140109981} is an apocalyptic number.

It is an amenable number.

1231140109981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231140109981 is an equidigital number, since it uses as much as digits as its factorization.

1231140109981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 40.

The spelling of 1231140109981 in words is "one trillion, two hundred thirty-one billion, one hundred forty million, one hundred nine thousand, nine hundred eighty-one".