121899520512 has 800 divisors, whose sum is σ = 462017571840. Its totient is φ = 31077457920.

The previous prime is 121899520441. The next prime is 121899520597. The reversal of 121899520512 is 215025998121.

It is a happy number.

121899520512 is a `hidden beast` number, since 1 + 2 + 1 + 89 + 9 + 52 + 0 + 512 = 666.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

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 79 ways as a sum of consecutive naturals, for example, 188406973 + ... + 188407619.

Almost surely, 2^121899520512 is an apocalyptic number.

121899520512 is a gapful number since it is divisible by the number (12) 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 121899520512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (231008785920).

121899520512 is an abundant number, since it is smaller than the sum of its proper divisors (340118051328).

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

121899520512 is an equidigital number, since it uses as much as digits as its factorization.

121899520512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 754 (or 729 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 45.

It can be divided in two parts, 121899 and 520512, that added together give a triangular number (642411 = T₁₁₃₃).

The spelling of 121899520512 in words is "one hundred twenty-one billion, eight hundred ninety-nine million, five hundred twenty thousand, five hundred twelve".