218915409103109 has 2 divisors, whose sum is σ = 218915409103110. Its totient is φ = 218915409103108.

The previous prime is 218915409103103. The next prime is 218915409103129. The reversal of 218915409103109 is 901301904519812.

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., 111065314795009 + 107850094308100 = 10538753^2 + 10385090^2 .

It is a cyclic number.

It is not a de Polignac number, because 218915409103109 - 2²⁰ = 218915408054533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218915409103103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109457704551554 + 109457704551555.

It is an arithmetic number, because the mean of its divisors is an integer number (109457704551555).

Almost surely, 2^{218915409103109} is an apocalyptic number.

It is an amenable number.

218915409103109 is a deficient number, since it is larger than the sum of its proper divisors (1).

218915409103109 is an equidigital number, since it uses as much as digits as its factorization.

218915409103109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 699840, while the sum is 53.

The spelling of 218915409103109 in words is "two hundred eighteen trillion, nine hundred fifteen billion, four hundred nine million, one hundred three thousand, one hundred nine".