121257217 has 2 divisors, whose sum is σ = 121257218. Its totient is φ = 121257216.

The previous prime is 121257121. The next prime is 121257239. The reversal of 121257217 is 712752121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78694641 + 42562576 = 8871^2 + 6524^2 .

It is a cyclic number.

It is not a de Polignac number, because 121257217 - 2¹⁵ = 121224449 is a prime.

It is not a weakly prime, because it can be changed into another prime (121257247) 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, 60628608 + 60628609.

It is an arithmetic number, because the mean of its divisors is an integer number (60628609).

Almost surely, 2^121257217 is an apocalyptic number.

It is an amenable number.

121257217 is a deficient number, since it is larger than the sum of its proper divisors (1).

121257217 is an equidigital number, since it uses as much as digits as its factorization.

121257217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1960, while the sum is 28.

The square root of 121257217 is about 11011.6854749852. The cubic root of 121257217 is about 494.9589694930.

The spelling of 121257217 in words is "one hundred twenty-one million, two hundred fifty-seven thousand, two hundred seventeen".