121398817 has 2 divisors, whose sum is σ = 121398818. Its totient is φ = 121398816.

The previous prime is 121398803. The next prime is 121398839. The reversal of 121398817 is 718893121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73290721 + 48108096 = 8561^2 + 6936^2 .

It is an emirp because it is prime and its reverse (718893121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121398817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121398817.

It is not a weakly prime, because it can be changed into another prime (121398857) 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, 60699408 + 60699409.

It is an arithmetic number, because the mean of its divisors is an integer number (60699409).

Almost surely, 2^121398817 is an apocalyptic number.

It is an amenable number.

121398817 is a deficient number, since it is larger than the sum of its proper divisors (1).

121398817 is an equidigital number, since it uses as much as digits as its factorization.

121398817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 40.

The square root of 121398817 is about 11018.1131324742. The cubic root of 121398817 is about 495.1515598891.

The spelling of 121398817 in words is "one hundred twenty-one million, three hundred ninety-eight thousand, eight hundred seventeen".