1813948109 has 2 divisors, whose sum is σ = 1813948110. Its totient is φ = 1813948108.

The previous prime is 1813948079. The next prime is 1813948133. The reversal of 1813948109 is 9018493181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1530530884 + 283417225 = 39122^2 + 16835^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1813948109 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1813948109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1813948139) 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, 906974054 + 906974055.

It is an arithmetic number, because the mean of its divisors is an integer number (906974055).

Almost surely, 2^1813948109 is an apocalyptic number.

It is an amenable number.

1813948109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1813948109 is an equidigital number, since it uses as much as digits as its factorization.

1813948109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 44.

The square root of 1813948109 is about 42590.4696968700. The cubic root of 1813948109 is about 1219.5743630759.

The spelling of 1813948109 in words is "one billion, eight hundred thirteen million, nine hundred forty-eight thousand, one hundred nine".