12105543409 has 2 divisors, whose sum is σ = 12105543410. Its totient is φ = 12105543408.

The previous prime is 12105543377. The next prime is 12105543469. The reversal of 12105543409 is 90434550121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10966278400 + 1139265009 = 104720^2 + 33753^2 .

It is a cyclic number.

It is not a de Polignac number, because 12105543409 - 2⁵ = 12105543377 is a prime.

It is not a weakly prime, because it can be changed into another prime (12105543469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6052771704 + 6052771705.

It is an arithmetic number, because the mean of its divisors is an integer number (6052771705).

Almost surely, 2^12105543409 is an apocalyptic number.

It is an amenable number.

12105543409 is a deficient number, since it is larger than the sum of its proper divisors (1).

12105543409 is an equidigital number, since it uses as much as digits as its factorization.

12105543409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 34.

The spelling of 12105543409 in words is "twelve billion, one hundred five million, five hundred forty-three thousand, four hundred nine".