218561536 has 44 divisors (see below), whose sum is σ = 444199000. Its totient is φ = 107458560.

The previous prime is 218561533. The next prime is 218561543. The reversal of 218561536 is 635165812.

It is a junction number, because it is equal to n+sod(n) for n = 218561495 and 218561504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218561533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60715 + ... + 64213.

Almost surely, 2^218561536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218561536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222099500).

218561536 is an abundant number, since it is smaller than the sum of its proper divisors (225637464).

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

218561536 is an equidigital number, since it uses as much as digits as its factorization.

218561536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3580 (or 3562 counting only the distinct ones).

The product of its digits is 43200, while the sum is 37.

The square root of 218561536 is about 14783.8268388127. The cubic root of 218561536 is about 602.3624782114.

The spelling of 218561536 in words is "two hundred eighteen million, five hundred sixty-one thousand, five hundred thirty-six".