13231561728 has 528 divisors, whose sum is σ = 45835244928. Its totient is φ = 3354624000.

The previous prime is 13231561727. The next prime is 13231561729. The reversal of 13231561728 is 82716513231.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (13231561727) and next prime (13231561729).

It is a tau number, because it is divible by the number of its divisors (528).

Its product of digits (60480) is a multiple of the sum of its prime factors (240).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13231561723) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 101004223 + ... + 101004353.

It is an arithmetic number, because the mean of its divisors is an integer number (86809176).

Almost surely, 2^13231561728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13231561728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22917622464).

13231561728 is an abundant number, since it is smaller than the sum of its proper divisors (32603683200).

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

13231561728 is a wasteful number, since it uses less digits than its factorization.

13231561728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240 (or 215 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The spelling of 13231561728 in words is "thirteen billion, two hundred thirty-one million, five hundred sixty-one thousand, seven hundred twenty-eight".