121989121 has 2 divisors, whose sum is σ = 121989122. Its totient is φ = 121989120.

The previous prime is 121989107. The next prime is 121989143.

121989121 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121859521 + 129600 = 11039^2 + 360^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 121989121 - 2⁵ = 121989089 is a prime.

It is a super-3 number, since 3×121989121³ (a number of 25 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (121989191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60994560 + 60994561.

It is an arithmetic number, because the mean of its divisors is an integer number (60994561).

Almost surely, 2^121989121 is an apocalyptic number.

It is an amenable number.

121989121 is a deficient number, since it is larger than the sum of its proper divisors (1).

121989121 is an equidigital number, since it uses as much as digits as its factorization.

121989121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 34.

The square root of 121989121 is about 11044.8685370175. The cubic root of 121989121 is about 495.9528237844.

The spelling of 121989121 in words is "one hundred twenty-one million, nine hundred eighty-nine thousand, one hundred twenty-one".