13641205840 has 40 divisors (see below), whose sum is σ = 31795766280. Its totient is φ = 5442725376.

The previous prime is 13641205813. The next prime is 13641205847. The reversal of 13641205840 is 4850214631.

It can be written as a sum of positive squares in 4 ways, for example, as 6579156544 + 7062049296 = 81112^2 + 84036^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 13641205796 and 13641205805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13641205847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 182995 + ... + 246514.

It is an arithmetic number, because the mean of its divisors is an integer number (794894157).

Almost surely, 2^13641205840 is an apocalyptic number.

13641205840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13641205840 is an abundant number, since it is smaller than the sum of its proper divisors (18154560440).

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

13641205840 is a wasteful number, since it uses less digits than its factorization.

13641205840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 429919 (or 429913 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 34.

The spelling of 13641205840 in words is "thirteen billion, six hundred forty-one million, two hundred five thousand, eight hundred forty".