11981286720 has 840 divisors, whose sum is σ = 48708103752. Its totient is φ = 2776965120.

The previous prime is 11981286697. The next prime is 11981286727. The reversal of 11981286720 is 2768218911.

It can be written as a sum of positive squares in 4 ways, for example, as 1439747136 + 10541539584 = 37944^2 + 102672^2 .

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 (11981286727) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 323818542 + ... + 323818578.

Almost surely, 2^11981286720 is an apocalyptic number.

11981286720 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 11981286720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24354051876).

11981286720 is an abundant number, since it is smaller than the sum of its proper divisors (36726817032).

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

11981286720 is a wasteful number, since it uses less digits than its factorization.

11981286720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 45.

The spelling of 11981286720 in words is "eleven billion, nine hundred eighty-one million, two hundred eighty-six thousand, seven hundred twenty".