121809113 has 2 divisors, whose sum is σ = 121809114. Its totient is φ = 121809112.

The previous prime is 121809109. The next prime is 121809119. The reversal of 121809113 is 311908121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110733529 + 11075584 = 10523^2 + 3328^2 .

It is a cyclic number.

It is not a de Polignac number, because 121809113 - 2² = 121809109 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 (121809119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60904556 + 60904557.

It is an arithmetic number, because the mean of its divisors is an integer number (60904557).

Almost surely, 2^121809113 is an apocalyptic number.

It is an amenable number.

121809113 is a deficient number, since it is larger than the sum of its proper divisors (1).

121809113 is an equidigital number, since it uses as much as digits as its factorization.

121809113 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 26.

The square root of 121809113 is about 11036.7165860142. The cubic root of 121809113 is about 495.7087598792.

The spelling of 121809113 in words is "one hundred twenty-one million, eight hundred nine thousand, one hundred thirteen".