12543721650 has 36 divisors (see below), whose sum is σ = 33700800042. Its totient is φ = 3344992320.

The previous prime is 12543721639. The next prime is 12543721667. The reversal of 12543721650 is 5612734521.

12543721650 is a `hidden beast` number, since 1 + 2 + 5 + 437 + 216 + 5 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 6104140641 + 6439581009 = 78129^2 + 80247^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 13937019 + ... + 13937918.

Almost surely, 2^12543721650 is an apocalyptic number.

12543721650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12543721650 is an abundant number, since it is smaller than the sum of its proper divisors (21157078392).

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

12543721650 is a wasteful number, since it uses less digits than its factorization.

12543721650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27874955 (or 27874947 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The spelling of 12543721650 in words is "twelve billion, five hundred forty-three million, seven hundred twenty-one thousand, six hundred fifty".