12081491856 has 120 divisors (see below), whose sum is σ = 38663936064. Its totient is φ = 3449859840.

The previous prime is 12081491801. The next prime is 12081491909. The reversal of 12081491856 is 65819418021.

It is a happy number.

12081491856 is a `hidden beast` number, since 1 + 2 + 0 + 81 + 491 + 85 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3371986 + ... + 3375566.

Almost surely, 2^12081491856 is an apocalyptic number.

12081491856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

12081491856 is an abundant number, since it is smaller than the sum of its proper divisors (26582444208).

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

12081491856 is a wasteful number, since it uses less digits than its factorization.

12081491856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6949 (or 6940 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 45.

The spelling of 12081491856 in words is "twelve billion, eighty-one million, four hundred ninety-one thousand, eight hundred fifty-six".