13605818420 has 24 divisors (see below), whose sum is σ = 30252938184. Its totient is φ = 5122190336.

The previous prime is 13605818417. The next prime is 13605818441. The reversal of 13605818420 is 2481850631.

It can be written as a sum of positive squares in 4 ways, for example, as 1847452324 + 11758366096 = 42982^2 + 108436^2 .

It is a super-2 number, since 2×13605818420² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20008217 + ... + 20008896.

It is an arithmetic number, because the mean of its divisors is an integer number (1260539091).

Almost surely, 2^13605818420 is an apocalyptic number.

13605818420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13605818420 is an abundant number, since it is smaller than the sum of its proper divisors (16647119764).

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

13605818420 is a wasteful number, since it uses less digits than its factorization.

13605818420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40017139 (or 40017137 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The spelling of 13605818420 in words is "thirteen billion, six hundred five million, eight hundred eighteen thousand, four hundred twenty".