121543958989 has 2 divisors, whose sum is σ = 121543958990. Its totient is φ = 121543958988.

The previous prime is 121543958981. The next prime is 121543959109. The reversal of 121543958989 is 989859345121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 108938283364 + 12605675625 = 330058^2 + 112275^2 .

It is a cyclic number.

It is not a de Polignac number, because 121543958989 - 2³ = 121543958981 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121543958989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121543958981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60771979494 + 60771979495.

It is an arithmetic number, because the mean of its divisors is an integer number (60771979495).

Almost surely, 2^121543958989 is an apocalyptic number.

It is an amenable number.

121543958989 is a deficient number, since it is larger than the sum of its proper divisors (1).

121543958989 is an equidigital number, since it uses as much as digits as its factorization.

121543958989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27993600, while the sum is 64.

The spelling of 121543958989 in words is "one hundred twenty-one billion, five hundred forty-three million, nine hundred fifty-eight thousand, nine hundred eighty-nine".