121892909 has 2 divisors, whose sum is σ = 121892910. Its totient is φ = 121892908.

The previous prime is 121892863. The next prime is 121892957. The reversal of 121892909 is 909298121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112572100 + 9320809 = 10610^2 + 3053^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121892909 is a prime.

It is a Sophie Germain prime.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121892509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60946454 + 60946455.

It is an arithmetic number, because the mean of its divisors is an integer number (60946455).

Almost surely, 2^121892909 is an apocalyptic number.

It is an amenable number.

121892909 is a deficient number, since it is larger than the sum of its proper divisors (1).

121892909 is an equidigital number, since it uses as much as digits as its factorization.

121892909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 121892909 is about 11040.5121710906. The cubic root of 121892909 is about 495.8224046050.

The spelling of 121892909 in words is "one hundred twenty-one million, eight hundred ninety-two thousand, nine hundred nine".