13643520768 has 162 divisors, whose sum is σ = 40853573124. Its totient is φ = 4547280384.

The previous prime is 13643520727. The next prime is 13643520769. The reversal of 13643520768 is 86702534631.

13643520768 is a `hidden beast` number, since 1 + 3 + 6 + 435 + 207 + 6 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (162).

It is a super-2 number, since 2×13643520768² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13643520769) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1675555 + ... + 1683677.

Almost surely, 2^13643520768 is an apocalyptic number.

13643520768 is a gapful number since it is divisible by the number (18) 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 13643520768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20426786562).

13643520768 is an abundant number, since it is smaller than the sum of its proper divisors (27210052356).

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

13643520768 is an frugal number, since it uses more digits than its factorization.

13643520768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8163 (or 8128 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 13643520768 in words is "thirteen billion, six hundred forty-three million, five hundred twenty thousand, seven hundred sixty-eight".