13531581856 has 48 divisors (see below), whose sum is σ = 28943546184. Its totient is φ = 6190055424.

The previous prime is 13531581827. The next prime is 13531581907. The reversal of 13531581856 is 65818513531.

It can be written as a sum of positive squares in 4 ways, for example, as 6869757456 + 6661824400 = 82884^2 + 81620^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96921 + ... + 190936.

Almost surely, 2^13531581856 is an apocalyptic number.

13531581856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

13531581856 is an abundant number, since it is smaller than the sum of its proper divisors (15411964328).

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

13531581856 is a wasteful number, since it uses less digits than its factorization.

13531581856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287993 (or 287985 counting only the distinct ones).

The product of its digits is 432000, while the sum is 46.

The spelling of 13531581856 in words is "thirteen billion, five hundred thirty-one million, five hundred eighty-one thousand, eight hundred fifty-six".