12811309056 has 832 divisors, whose sum is σ = 49906124800. Its totient is φ = 3153199104.

The previous prime is 12811309009. The next prime is 12811309057. The reversal of 12811309056 is 65090311821.

It is a tau number, because it is divible by the number of its divisors (832).

It is a super-2 number, since 2×12811309056² (a number of 21 digits) contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 12811309056.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12811309057) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 191213535 + ... + 191213601.

Almost surely, 2^12811309056 is an apocalyptic number.

12811309056 is a gapful number since it is divisible by the number (16) 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 12811309056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24953062400).

12811309056 is an abundant number, since it is smaller than the sum of its proper divisors (37094815744).

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

12811309056 is a wasteful number, since it uses less digits than its factorization.

12811309056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 12811309056 in words is "twelve billion, eight hundred eleven million, three hundred nine thousand, fifty-six".