12291056640 has 616 divisors, whose sum is σ = 45910852920. Its totient is φ = 3153199104.

The previous prime is 12291056599. The next prime is 12291056671. The reversal of 12291056640 is 4665019221.

12291056640 is a `hidden beast` number, since 1 + 2 + 2 + 9 + 1 + 0 + 5 + 6 + 640 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1719926784 + 10571129856 = 41472^2 + 102816^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 12291056595 and 12291056604.

It is a congruent number.

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 55 ways as a sum of consecutive naturals, for example, 138101716 + ... + 138101804.

Almost surely, 2^12291056640 is an apocalyptic number.

12291056640 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 12291056640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22955426460).

12291056640 is an abundant number, since it is smaller than the sum of its proper divisors (33619796280).

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

12291056640 is an frugal number, since it uses more digits than its factorization.

12291056640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169 (or 136 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 12291056640 in words is "twelve billion, two hundred ninety-one million, fifty-six thousand, six hundred forty".