12181654631520 has 480 divisors, whose sum is σ = 48166941737376. Its totient is φ = 2873312870400.

The previous prime is 12181654631491. The next prime is 12181654631521. The reversal of 12181654631520 is 2513645618121.

12181654631520 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 1 + 6 + 5 + 4 + 631 + 5 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

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 a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12181654631521) by changing a digit.

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 79 ways as a sum of consecutive naturals, for example, 4120000 + ... + 6429440.

Almost surely, 2^{12181654631520} is an apocalyptic number.

12181654631520 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 12181654631520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24083470868688).

12181654631520 is an abundant number, since it is smaller than the sum of its proper divisors (35985287105856).

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

12181654631520 is a wasteful number, since it uses less digits than its factorization.

12181654631520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2309516 (or 2309499 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The spelling of 12181654631520 in words is "twelve trillion, one hundred eighty-one billion, six hundred fifty-four million, six hundred thirty-one thousand, five hundred twenty".