121555513080144 has 720 divisors, whose sum is σ = 424800792509184. Its totient is φ = 31982708736000.

The previous prime is 121555513080011. The next prime is 121555513080191. The reversal of 121555513080144 is 441080315555121.

121555513080144 is a `hidden beast` number, since 1 + 2 + 1 + 5 + 5 + 551 + 3 + 0 + 80 + 14 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 121555513080144.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 12277089594 + ... + 12277099494.

Almost surely, 2^{121555513080144} 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 121555513080144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212400396254592).

121555513080144 is an abundant number, since it is smaller than the sum of its proper divisors (303245279429040).

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

121555513080144 is a wasteful number, since it uses less digits than its factorization.

121555513080144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12036 (or 12010 counting only the distinct ones).

The product of its (nonzero) digits is 480000, while the sum is 45.

The spelling of 121555513080144 in words is "one hundred twenty-one trillion, five hundred fifty-five billion, five hundred thirteen million, eighty thousand, one hundred forty-four".