121389989 has 8 divisors (see below), whose sum is σ = 141958080. Its totient is φ = 101628576.

The previous prime is 121389977. The next prime is 121390019. The reversal of 121389989 is 989983121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121389989 - 2¹² = 121385893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121389959) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 201344 + ... + 201945.

It is an arithmetic number, because the mean of its divisors is an integer number (17744760).

Almost surely, 2^121389989 is an apocalyptic number.

It is an amenable number.

121389989 is a deficient number, since it is larger than the sum of its proper divisors (20568091).

121389989 is an equidigital number, since it uses as much as digits as its factorization.

121389989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403339.

The product of its digits is 279936, while the sum is 50.

The square root of 121389989 is about 11017.7125121325. The cubic root of 121389989 is about 495.1395572902.

The spelling of 121389989 in words is "one hundred twenty-one million, three hundred eighty-nine thousand, nine hundred eighty-nine".