13638821859 has 24 divisors (see below), whose sum is σ = 21789355952. Its totient is φ = 8166277440.

The previous prime is 13638821857. The next prime is 13638821869. The reversal of 13638821859 is 95812883631.

It is not a de Polignac number, because 13638821859 - 2¹ = 13638821857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13638821857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1570957 + ... + 1579614.

Almost surely, 2^13638821859 is an apocalyptic number.

13638821859 is a deficient number, since it is larger than the sum of its proper divisors (8150534093).

13638821859 is a wasteful number, since it uses less digits than its factorization.

13638821859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3150627 (or 3150624 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 54.

The spelling of 13638821859 in words is "thirteen billion, six hundred thirty-eight million, eight hundred twenty-one thousand, eight hundred fifty-nine".