121531374720 has 768 divisors, whose sum is σ = 494682439680. Its totient is φ = 26916986880.

The previous prime is 121531374719. The next prime is 121531374733. The reversal of 121531374720 is 27473135121.

121531374720 is a `hidden beast` number, since 1 + 2 + 1 + 53 + 137 + 472 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 331147977 + ... + 331148343.

It is an arithmetic number, because the mean of its divisors is an integer number (644117760).

Almost surely, 2^121531374720 is an apocalyptic number.

121531374720 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 121531374720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (247341219840).

121531374720 is an abundant number, since it is smaller than the sum of its proper divisors (373151064960).

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

121531374720 is a wasteful number, since it uses less digits than its factorization.

121531374720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633 (or 618 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The spelling of 121531374720 in words is "one hundred twenty-one billion, five hundred thirty-one million, three hundred seventy-four thousand, seven hundred twenty".