123220555109 has 2 divisors, whose sum is σ = 123220555110. Its totient is φ = 123220555108.

The previous prime is 123220555103. The next prime is 123220555151. The reversal of 123220555109 is 901555022321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75542522500 + 47678032609 = 274850^2 + 218353^2 .

It is a cyclic number.

It is not a de Polignac number, because 123220555109 - 2²⁰ = 123219506533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123220555103) 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, 61610277554 + 61610277555.

It is an arithmetic number, because the mean of its divisors is an integer number (61610277555).

Almost surely, 2^123220555109 is an apocalyptic number.

It is an amenable number.

123220555109 is a deficient number, since it is larger than the sum of its proper divisors (1).

123220555109 is an equidigital number, since it uses as much as digits as its factorization.

123220555109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27000, while the sum is 35.

The spelling of 123220555109 in words is "one hundred twenty-three billion, two hundred twenty million, five hundred fifty-five thousand, one hundred nine".