12736549566 has 128 divisors (see below), whose sum is σ = 33972825600. Its totient is φ = 3494223360.

The previous prime is 12736549559. The next prime is 12736549577. The reversal of 12736549566 is 66594563721.

12736549566 is a `hidden beast` number, since 1 + 2 + 7 + 36 + 5 + 49 + 566 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 198661 + ... + 254831.

It is an arithmetic number, because the mean of its divisors is an integer number (265412700).

Almost surely, 2^12736549566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12736549566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16986412800).

12736549566 is an abundant number, since it is smaller than the sum of its proper divisors (21236276034).

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

12736549566 is a wasteful number, since it uses less digits than its factorization.

12736549566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56231 (or 56225 counting only the distinct ones).

The product of its digits is 8164800, while the sum is 54.

The spelling of 12736549566 in words is "twelve billion, seven hundred thirty-six million, five hundred forty-nine thousand, five hundred sixty-six".