121621889 has 2 divisors, whose sum is σ = 121621890. Its totient is φ = 121621888.

The previous prime is 121621847. The next prime is 121621937. The reversal of 121621889 is 988126121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90630400 + 30991489 = 9520^2 + 5567^2 .

It is an emirp because it is prime and its reverse (988126121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121621889 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (121621589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60810944 + 60810945.

It is an arithmetic number, because the mean of its divisors is an integer number (60810945).

Almost surely, 2^121621889 is an apocalyptic number.

It is an amenable number.

121621889 is a deficient number, since it is larger than the sum of its proper divisors (1).

121621889 is an equidigital number, since it uses as much as digits as its factorization.

121621889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 38.

The square root of 121621889 is about 11028.2314538642. The cubic root of 121621889 is about 495.4546569225.

The spelling of 121621889 in words is "one hundred twenty-one million, six hundred twenty-one thousand, eight hundred eighty-nine".