113781809 has 2 divisors, whose sum is σ = 113781810. Its totient is φ = 113781808.

The previous prime is 113781803. The next prime is 113781817. The reversal of 113781809 is 908187311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110986225 + 2795584 = 10535^2 + 1672^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-113781809 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 (113781803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 56890904 + 56890905.

It is an arithmetic number, because the mean of its divisors is an integer number (56890905).

Almost surely, 2^113781809 is an apocalyptic number.

It is an amenable number.

113781809 is a deficient number, since it is larger than the sum of its proper divisors (1).

113781809 is an equidigital number, since it uses as much as digits as its factorization.

113781809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 38.

The square root of 113781809 is about 10666.8556285346. The cubic root of 113781809 is about 484.5712141800.

The spelling of 113781809 in words is "one hundred thirteen million, seven hundred eighty-one thousand, eight hundred nine".