121218440 has 32 divisors (see below), whose sum is σ = 311705280. Its totient is φ = 41560512.

The previous prime is 121218431. The next prime is 121218443. The reversal of 121218440 is 44812121.

It is not an unprimeable number, because it can be changed into a prime (121218443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216182 + ... + 216741.

It is an arithmetic number, because the mean of its divisors is an integer number (9740790).

Almost surely, 2^121218440 is an apocalyptic number.

121218440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121218440 is an abundant number, since it is smaller than the sum of its proper divisors (190486840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121218440 is a wasteful number, since it uses less digits than its factorization.

121218440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432941 (or 432937 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 23.

The square root of 121218440 is about 11009.9246137292. The cubic root of 121218440 is about 494.9062026812.

The spelling of 121218440 in words is "one hundred twenty-one million, two hundred eighteen thousand, four hundred forty".