121716909 has 6 divisors (see below), whose sum is σ = 175813326. Its totient is φ = 81144600.

The previous prime is 121716901. The next prime is 121716911. The reversal of 121716909 is 909617121.

It can be written as a sum of positive squares in only one way, i.e., 119902500 + 1814409 = 10950^2 + 1347^2 .

It is not a de Polignac number, because 121716909 - 2³ = 121716901 is a prime.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121716901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6762042 + ... + 6762059.

It is an arithmetic number, because the mean of its divisors is an integer number (29302221).

Almost surely, 2^121716909 is an apocalyptic number.

It is an amenable number.

121716909 is a deficient number, since it is larger than the sum of its proper divisors (54096417).

121716909 is a wasteful number, since it uses less digits than its factorization.

121716909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13524107 (or 13524104 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 36.

The square root of 121716909 is about 11032.5386471111. The cubic root of 121716909 is about 495.5836519220.

The spelling of 121716909 in words is "one hundred twenty-one million, seven hundred sixteen thousand, nine hundred nine".