12561499968 has 56 divisors (see below), whose sum is σ = 34046281920. Its totient is φ = 4085038080.

The previous prime is 12561499957. The next prime is 12561499999. The reversal of 12561499968 is 86999416521.

It is a congruent number.

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, 789988 + ... + 805731.

It is an arithmetic number, because the mean of its divisors is an integer number (607969320).

Almost surely, 2^12561499968 is an apocalyptic number.

It is an amenable number.

12561499968 is an abundant number, since it is smaller than the sum of its proper divisors (21484781952).

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

12561499968 is a wasteful number, since it uses less digits than its factorization.

12561499968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1595775 (or 1595765 counting only the distinct ones).

The product of its digits is 8398080, while the sum is 60.

The spelling of 12561499968 in words is "twelve billion, five hundred sixty-one million, four hundred ninety-nine thousand, nine hundred sixty-eight".