121638124608 has 448 divisors, whose sum is σ = 433329039360. Its totient is φ = 29082009600.

The previous prime is 121638124591. The next prime is 121638124613. The reversal of 121638124608 is 806421836121.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 121638124608.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 94365628 + ... + 94366916.

It is an arithmetic number, because the mean of its divisors is an integer number (967252320).

Almost surely, 2^121638124608 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121638124608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (216664519680).

121638124608 is an abundant number, since it is smaller than the sum of its proper divisors (311690914752).

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

121638124608 is a wasteful number, since it uses less digits than its factorization.

121638124608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1826 (or 1816 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 42.

The spelling of 121638124608 in words is "one hundred twenty-one billion, six hundred thirty-eight million, one hundred twenty-four thousand, six hundred eight".