121680217 has 2 divisors, whose sum is σ = 121680218. Its totient is φ = 121680216.

The previous prime is 121680211. The next prime is 121680277. The reversal of 121680217 is 712086121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70829056 + 50851161 = 8416^2 + 7131^2 .

It is an emirp because it is prime and its reverse (712086121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121680217 - 2⁷ = 121680089 is a prime.

It is a super-3 number, since 3×121680217³ (a number of 25 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (121680211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60840108 + 60840109.

It is an arithmetic number, because the mean of its divisors is an integer number (60840109).

Almost surely, 2^121680217 is an apocalyptic number.

It is an amenable number.

121680217 is a deficient number, since it is larger than the sum of its proper divisors (1).

121680217 is an equidigital number, since it uses as much as digits as its factorization.

121680217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 121680217 is about 11030.8756225424. The cubic root of 121680217 is about 495.5338484257.

The spelling of 121680217 in words is "one hundred twenty-one million, six hundred eighty thousand, two hundred seventeen".