12784400440 has 128 divisors (see below), whose sum is σ = 33671946240. Its totient is φ = 4277408256.

The previous prime is 12784400423. The next prime is 12784400491. The reversal of 12784400440 is 4400448721.

It is a super-2 number, since 2×12784400440² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 12784400396 and 12784400405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5223297 + ... + 5225743.

It is an arithmetic number, because the mean of its divisors is an integer number (263062080).

Almost surely, 2^12784400440 is an apocalyptic number.

12784400440 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 12784400440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16835973120).

12784400440 is an abundant number, since it is smaller than the sum of its proper divisors (20887545800).

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

12784400440 is a wasteful number, since it uses less digits than its factorization.

12784400440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2909 (or 2905 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 34.

The spelling of 12784400440 in words is "twelve billion, seven hundred eighty-four million, four hundred thousand, four hundred forty".