12991555184400 has 405 divisors, whose sum is σ = 48829666677597. Its totient is φ = 3197229235200.

The previous prime is 12991555184389. The next prime is 12991555184501. The reversal of 12991555184400 is 448155519921.

The square root of 12991555184400 is 3604380.

It is a perfect power (a square), and thus also a powerful number.

12991555184400 is a `hidden beast` number, since 1 + 2 + 9 + 9 + 1 + 5 + 55 + 184 + 400 = 666.

It can be written as a sum of positive squares in 13 ways, for example, as 12792325076496 + 199230107904 = 3576636^2 + 446352^2 .

It is a super-2 number, since 2×12991555184400² (a number of 27 digits) contains 22 as substring.

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 80 ways as a sum of consecutive naturals, for example, 2811414090 + ... + 2811418710.

Almost surely, 2^{12991555184400} is an apocalyptic number.

12991555184400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12991555184400 is the 3604380-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12991555184400

12991555184400 is an abundant number, since it is smaller than the sum of its proper divisors (35838111493197).

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

12991555184400 is an equidigital number, since it uses as much as digits as its factorization.

12991555184400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9292 (or 4644 counting only the distinct ones).

The product of its (nonzero) digits is 2592000, while the sum is 54.

The spelling of 12991555184400 in words is "twelve trillion, nine hundred ninety-one billion, five hundred fifty-five million, one hundred eighty-four thousand, four hundred".