121121222009 has 2 divisors, whose sum is σ = 121121222010. Its totient is φ = 121121222008.

The previous prime is 121121222003. The next prime is 121121222041. The reversal of 121121222009 is 900222121121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 118011486784 + 3109735225 = 343528^2 + 55765^2 .

It is an emirp because it is prime and its reverse (900222121121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121121222009 - 2⁴ = 121121221993 is a prime.

It is not a weakly prime, because it can be changed into another prime (121121222003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60560611004 + 60560611005.

It is an arithmetic number, because the mean of its divisors is an integer number (60560611005).

Almost surely, 2^121121222009 is an apocalyptic number.

It is an amenable number.

121121222009 is a deficient number, since it is larger than the sum of its proper divisors (1).

121121222009 is an equidigital number, since it uses as much as digits as its factorization.

121121222009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 23.

The spelling of 121121222009 in words is "one hundred twenty-one billion, one hundred twenty-one million, two hundred twenty-two thousand, nine".