121356817 has 2 divisors, whose sum is σ = 121356818. Its totient is φ = 121356816.

The previous prime is 121356787. The next prime is 121356881. The reversal of 121356817 is 718653121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 100781521 + 20575296 = 10039^2 + 4536^2 .

It is a cyclic number.

It is not a de Polignac number, because 121356817 - 2¹¹ = 121354769 is a prime.

It is not a weakly prime, because it can be changed into another prime (121356887) 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, 60678408 + 60678409.

It is an arithmetic number, because the mean of its divisors is an integer number (60678409).

Almost surely, 2^121356817 is an apocalyptic number.

It is an amenable number.

121356817 is a deficient number, since it is larger than the sum of its proper divisors (1).

121356817 is an equidigital number, since it uses as much as digits as its factorization.

121356817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 34.

The square root of 121356817 is about 11016.2070151209. The cubic root of 121356817 is about 495.0944512484.

The spelling of 121356817 in words is "one hundred twenty-one million, three hundred fifty-six thousand, eight hundred seventeen".