12564638334 has 48 divisors (see below), whose sum is σ = 28127983104. Its totient is φ = 4049298000.

The previous prime is 12564638287. The next prime is 12564638347. The reversal of 12564638334 is 43383646521.

12564638334 is a `hidden beast` number, since 1 + 2 + 5 + 6 + 4 + 638 + 3 + 3 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 12564638334.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 616609 + ... + 636659.

It is an arithmetic number, because the mean of its divisors is an integer number (585999648).

Almost surely, 2^12564638334 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12564638334, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14063991552).

12564638334 is an abundant number, since it is smaller than the sum of its proper divisors (15563344770).

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

12564638334 is a wasteful number, since it uses less digits than its factorization.

12564638334 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21213 (or 21210 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 45.

The spelling of 12564638334 in words is "twelve billion, five hundred sixty-four million, six hundred thirty-eight thousand, three hundred thirty-four".