1243242112109 has 2 divisors, whose sum is σ = 1243242112110. Its totient is φ = 1243242112108.

The previous prime is 1243242112081. The next prime is 1243242112241. The reversal of 1243242112109 is 9012112423421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1189292759209 + 53949352900 = 1090547^2 + 232270^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1243242112109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1243242112009) 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, 621621056054 + 621621056055.

It is an arithmetic number, because the mean of its divisors is an integer number (621621056055).

Almost surely, 2^{1243242112109} is an apocalyptic number.

It is an amenable number.

1243242112109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243242112109 is an equidigital number, since it uses as much as digits as its factorization.

1243242112109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 32.

The spelling of 1243242112109 in words is "one trillion, two hundred forty-three billion, two hundred forty-two million, one hundred twelve thousand, one hundred nine".