13205646720 has 384 divisors, whose sum is σ = 52416037440. Its totient is φ = 3001024512.

The previous prime is 13205646697. The next prime is 13205646721. The reversal of 13205646720 is 2764650231.

13205646720 is a `hidden beast` number, since 1 + 3 + 2 + 0 + 5 + 646 + 7 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13205646721) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7780912 + ... + 7782608.

Almost surely, 2^13205646720 is an apocalyptic number.

13205646720 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 13205646720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26208018720).

13205646720 is an abundant number, since it is smaller than the sum of its proper divisors (39210390720).

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

13205646720 is a wasteful number, since it uses less digits than its factorization.

13205646720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1922 (or 1907 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The spelling of 13205646720 in words is "thirteen billion, two hundred five million, six hundred forty-six thousand, seven hundred twenty".