42138786818 has 18 divisors (see below), whose sum is σ = 66086319747. Its totient is φ = 20150139460.

The previous prime is 42138786799. The next prime is 42138786871. The reversal of 42138786818 is 81868783124.

42138786818 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 21069393409 + 21069393409 = 145153^2 + 145153^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=145153.

It is a super-3 number, since 3×42138786818³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 6673883 + ... + 6680193.

Almost surely, 2^42138786818 is an apocalyptic number.

42138786818 is a deficient number, since it is larger than the sum of its proper divisors (23947532929).

42138786818 is an frugal number, since it uses more digits than its factorization.

42138786818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12670 (or 6336 counting only the distinct ones).

The product of its digits is 4128768, while the sum is 56.

The spelling of 42138786818 in words is "forty-two billion, one hundred thirty-eight million, seven hundred eighty-six thousand, eight hundred eighteen".