12991751840 has 48 divisors (see below), whose sum is σ = 30700078920. Its totient is φ = 5195504640.

The previous prime is 12991751803. The next prime is 12991751887. The reversal of 12991751840 is 4815719921.

It can be written as a sum of positive squares in 4 ways, for example, as 3798010384 + 9193741456 = 61628^2 + 95884^2 .

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, 1093130 + ... + 1104950.

Almost surely, 2^12991751840 is an apocalyptic number.

12991751840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12991751840 is an abundant number, since it is smaller than the sum of its proper divisors (17708327080).

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

12991751840 is a wasteful number, since it uses less digits than its factorization.

12991751840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18705 (or 18697 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 47.

The spelling of 12991751840 in words is "twelve billion, nine hundred ninety-one million, seven hundred fifty-one thousand, eight hundred forty".