121878916331520 has 192 divisors, whose sum is σ = 390109875442560. Its totient is φ = 32484993695744.

The previous prime is 121878916331429. The next prime is 121878916331539. The reversal of 121878916331520 is 25133619878121.

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×121878916331520² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61290799 + ... + 63248081.

It is an arithmetic number, because the mean of its divisors is an integer number (2031822267930).

Almost surely, 2^{121878916331520} is an apocalyptic number.

121878916331520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121878916331520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (195054937721280).

121878916331520 is an abundant number, since it is smaller than the sum of its proper divisors (268230959111040).

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

121878916331520 is a wasteful number, since it uses less digits than its factorization.

121878916331520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1959340 (or 1959320 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 57.

The spelling of 121878916331520 in words is "one hundred twenty-one trillion, eight hundred seventy-eight billion, nine hundred sixteen million, three hundred thirty-one thousand, five hundred twenty".