121818817 has 2 divisors, whose sum is σ = 121818818. Its totient is φ = 121818816.

The previous prime is 121818811. The next prime is 121818847. The reversal of 121818817 is 718818121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 119049921 + 2768896 = 10911^2 + 1664^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121818817 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (121818811) 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, 60909408 + 60909409.

It is an arithmetic number, because the mean of its divisors is an integer number (60909409).

Almost surely, 2^121818817 is an apocalyptic number.

It is an amenable number.

121818817 is a deficient number, since it is larger than the sum of its proper divisors (1).

121818817 is an equidigital number, since it uses as much as digits as its factorization.

121818817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7168, while the sum is 37.

The square root of 121818817 is about 11037.1562007611. The cubic root of 121818817 is about 495.7219231803.

The spelling of 121818817 in words is "one hundred twenty-one million, eight hundred eighteen thousand, eight hundred seventeen".