12561682500 has 600 divisors, whose sum is σ = 45008936280. Its totient is φ = 3041280000.

The previous prime is 12561682487. The next prime is 12561682501. The reversal of 12561682500 is 528616521.

12561682500 is a `hidden beast` number, since 12 + 5 + 61 + 6 + 82 + 500 = 666.

It can be written as a sum of positive squares in 20 ways, for example, as 12107481156 + 454201344 = 110034^2 + 21312^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (12561682501) by changing a digit.

It is a polite number, since it can be written in 199 ways as a sum of consecutive naturals, for example, 141142456 + ... + 141142544.

Almost surely, 2^12561682500 is an apocalyptic number.

12561682500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12561682500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22504468140).

12561682500 is an abundant number, since it is smaller than the sum of its proper divisors (32447253780).

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

12561682500 is a wasteful number, since it uses less digits than its factorization.

12561682500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 12561682500 in words is "twelve billion, five hundred sixty-one million, six hundred eighty-two thousand, five hundred".