121518720 has 288 divisors, whose sum is σ = 451861020. Its totient is φ = 30081024.

The previous prime is 121518713. The next prime is 121518739. The reversal of 121518720 is 27815121.

121518720 is a `hidden beast` number, since 121 + 518 + 7 + 20 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 90782784 + 30735936 = 9528^2 + 5544^2 .

It is a tau number, because it is divible by the number of its divisors (288).

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 35 ways as a sum of consecutive naturals, for example, 1664604 + ... + 1664676.

Almost surely, 2^121518720 is an apocalyptic number.

121518720 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 121518720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225930510).

121518720 is an abundant number, since it is smaller than the sum of its proper divisors (330342300).

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

121518720 is a wasteful number, since it uses less digits than its factorization.

121518720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 27.

The square root of 121518720 is about 11023.5529662627. The cubic root of 121518720 is about 495.3145230971.

The spelling of 121518720 in words is "one hundred twenty-one million, five hundred eighteen thousand, seven hundred twenty".