12521643650 has 24 divisors (see below), whose sum is σ = 23785799040. Its totient is φ = 4902089360.

The previous prime is 12521643643. The next prime is 12521643653. The reversal of 12521643650 is 5634612521.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 12521643650.

It is not an unprimeable number, because it can be changed into a prime (12521643653) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2661830 + ... + 2666529.

It is an arithmetic number, because the mean of its divisors is an integer number (991074960).

Almost surely, 2^12521643650 is an apocalyptic number.

12521643650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12521643650 is a deficient number, since it is larger than the sum of its proper divisors (11264155390).

12521643650 is a wasteful number, since it uses less digits than its factorization.

12521643650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5328418 (or 5328413 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 35.

The spelling of 12521643650 in words is "twelve billion, five hundred twenty-one million, six hundred forty-three thousand, six hundred fifty".