121218439 has 4 divisors (see below), whose sum is σ = 121390120. Its totient is φ = 121046760.

The previous prime is 121218431. The next prime is 121218443. The reversal of 121218439 is 934812121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121218439 - 2³ = 121218431 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121218439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121218431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 84777 + ... + 86194.

It is an arithmetic number, because the mean of its divisors is an integer number (30347530).

Almost surely, 2^121218439 is an apocalyptic number.

121218439 is a deficient number, since it is larger than the sum of its proper divisors (171681).

121218439 is an equidigital number, since it uses as much as digits as its factorization.

121218439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171680.

The product of its digits is 3456, while the sum is 31.

The square root of 121218439 is about 11009.9245683156. The cubic root of 121218439 is about 494.9062013203.

The spelling of 121218439 in words is "one hundred twenty-one million, two hundred eighteen thousand, four hundred thirty-nine".