121221011209709 has 2 divisors, whose sum is σ = 121221011209710. Its totient is φ = 121221011209708.

The previous prime is 121221011209687. The next prime is 121221011209747. The reversal of 121221011209709 is 907902110122121.

It is an a-pointer prime, because the next prime (121221011209747) can be obtained adding 121221011209709 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 92773690248100 + 28447320961609 = 9631910^2 + 5333603^2 .

It is a cyclic number.

It is not a de Polignac number, because 121221011209709 - 2²⁰ = 121221010161133 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121221011209759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60610505604854 + 60610505604855.

It is an arithmetic number, because the mean of its divisors is an integer number (60610505604855).

Almost surely, 2^{121221011209709} is an apocalyptic number.

It is an amenable number.

121221011209709 is a deficient number, since it is larger than the sum of its proper divisors (1).

121221011209709 is an equidigital number, since it uses as much as digits as its factorization.

121221011209709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 38.

The spelling of 121221011209709 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, eleven million, two hundred nine thousand, seven hundred nine".