1109723158981 has 2 divisors, whose sum is σ = 1109723158982. Its totient is φ = 1109723158980.

The previous prime is 1109723158979. The next prime is 1109723158997. The reversal of 1109723158981 is 1898513279011.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1106422081956 + 3301077025 = 1051866^2 + 57455^2 .

It is a cyclic number.

It is not a de Polignac number, because 1109723158981 - 2¹ = 1109723158979 is a prime.

It is a super-2 number, since 2×1109723158981² (a number of 25 digits) contains 22 as substring.

Together with 1109723158979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1109723158681) 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, 554861579490 + 554861579491.

It is an arithmetic number, because the mean of its divisors is an integer number (554861579491).

Almost surely, 2^{1109723158981} is an apocalyptic number.

It is an amenable number.

1109723158981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1109723158981 is an equidigital number, since it uses as much as digits as its factorization.

1109723158981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 55.

The spelling of 1109723158981 in words is "one trillion, one hundred nine billion, seven hundred twenty-three million, one hundred fifty-eight thousand, nine hundred eighty-one".