1811122409 has 2 divisors, whose sum is σ = 1811122410. Its totient is φ = 1811122408.

The previous prime is 1811122403. The next prime is 1811122429. The reversal of 1811122409 is 9042211181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1785316009 + 25806400 = 42253^2 + 5080^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1811122409 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1811122403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 905561204 + 905561205.

It is an arithmetic number, because the mean of its divisors is an integer number (905561205).

Almost surely, 2^1811122409 is an apocalyptic number.

It is an amenable number.

1811122409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1811122409 is an equidigital number, since it uses as much as digits as its factorization.

1811122409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 1811122409 is about 42557.2838536484. The cubic root of 1811122409 is about 1218.9407649704.

The spelling of 1811122409 in words is "one billion, eight hundred eleven million, one hundred twenty-two thousand, four hundred nine".