121907189 has 2 divisors, whose sum is σ = 121907190. Its totient is φ = 121907188.

The previous prime is 121907171. The next prime is 121907207. The reversal of 121907189 is 981709121.

It is a balanced prime because it is at equal distance from previous prime (121907171) and next prime (121907207).

It can be written as a sum of positive squares in only one way, i.e., 121374289 + 532900 = 11017^2 + 730^2 .

It is an emirp because it is prime and its reverse (981709121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121907189 is a prime.

It is a super-2 number, since 2×121907189² = 29722725459763442, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121907089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60953594 + 60953595.

It is an arithmetic number, because the mean of its divisors is an integer number (60953595).

Almost surely, 2^121907189 is an apocalyptic number.

It is an amenable number.

121907189 is a deficient number, since it is larger than the sum of its proper divisors (1).

121907189 is an equidigital number, since it uses as much as digits as its factorization.

121907189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 38.

The square root of 121907189 is about 11041.1588612790. The cubic root of 121907189 is about 495.8417660470.

The spelling of 121907189 in words is "one hundred twenty-one million, nine hundred seven thousand, one hundred eighty-nine".