20538712786218 has 64 divisors (see below), whose sum is σ = 45913771499904. Its totient is φ = 6070851968000.

The previous prime is 20538712786171. The next prime is 20538712786219. The reversal of 20538712786218 is 81268721783502.

It is not an unprimeable number, because it can be changed into a prime (20538712786219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13002280 + ... + 14496092.

It is an arithmetic number, because the mean of its divisors is an integer number (717402679686).

Almost surely, 2^{20538712786218} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20538712786218, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22956885749952).

20538712786218 is an abundant number, since it is smaller than the sum of its proper divisors (25375058713686).

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

20538712786218 is a wasteful number, since it uses less digits than its factorization.

20538712786218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1498951.

The product of its (nonzero) digits is 18063360, while the sum is 60.

The spelling of 20538712786218 in words is "twenty trillion, five hundred thirty-eight billion, seven hundred twelve million, seven hundred eighty-six thousand, two hundred eighteen".