12643236564 has 96 divisors (see below), whose sum is σ = 34720224000. Its totient is φ = 3579085440.

The previous prime is 12643236563. The next prime is 12643236569. The reversal of 12643236564 is 46563234621.

It is a happy number.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12643236563) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 434554 + ... + 462734.

It is an arithmetic number, because the mean of its divisors is an integer number (361669000).

Almost surely, 2^12643236564 is an apocalyptic number.

12643236564 is a gapful number since it is divisible by the number (14) 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 12643236564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17360112000).

12643236564 is an abundant number, since it is smaller than the sum of its proper divisors (22076987436).

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

12643236564 is a wasteful number, since it uses less digits than its factorization.

12643236564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28318 (or 28302 counting only the distinct ones).

The product of its digits is 622080, while the sum is 42.

The spelling of 12643236564 in words is "twelve billion, six hundred forty-three million, two hundred thirty-six thousand, five hundred sixty-four".