18126253109 has 2 divisors, whose sum is σ = 18126253110. Its totient is φ = 18126253108.

The previous prime is 18126253087. The next prime is 18126253163. The reversal of 18126253109 is 90135262181.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9867442225 + 8258810884 = 99335^2 + 90878^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18126253109 is a prime.

It is a super-2 number, since 2×18126253109² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18126253199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9063126554 + 9063126555.

It is an arithmetic number, because the mean of its divisors is an integer number (9063126555).

Almost surely, 2^18126253109 is an apocalyptic number.

It is an amenable number.

18126253109 is a deficient number, since it is larger than the sum of its proper divisors (1).

18126253109 is an equidigital number, since it uses as much as digits as its factorization.

18126253109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25920, while the sum is 38.

The spelling of 18126253109 in words is "eighteen billion, one hundred twenty-six million, two hundred fifty-three thousand, one hundred nine".