218138544186836 has 96 divisors (see below), whose sum is σ = 471138868569600. Its totient is φ = 86057632088064.

The previous prime is 218138544186811. The next prime is 218138544186839. The reversal of 218138544186836 is 638681445831812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218138544186839) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 301504976 + ... + 302227608.

It is an arithmetic number, because the mean of its divisors is an integer number (4907696547600).

Almost surely, 2^{218138544186836} is an apocalyptic number.

218138544186836 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218138544186836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235569434284800).

218138544186836 is an abundant number, since it is smaller than the sum of its proper divisors (253000324382764).

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

218138544186836 is a wasteful number, since it uses less digits than its factorization.

218138544186836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 724953 (or 724951 counting only the distinct ones).

The product of its digits is 212336640, while the sum is 68.

The spelling of 218138544186836 in words is "two hundred eighteen trillion, one hundred thirty-eight billion, five hundred forty-four million, one hundred eighty-six thousand, eight hundred thirty-six".