218531768 has 192 divisors, whose sum is σ = 564026400. Its totient is φ = 78382080.

The previous prime is 218531759. The next prime is 218531783. The reversal of 218531768 is 867135812.

It is a super-2 number, since 2×218531768² = 95512267250411648, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3582458 + ... + 3582518.

Almost surely, 2^218531768 is an apocalyptic number.

218531768 is a gapful number since it is divisible by the number (28) 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 218531768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (282013200).

218531768 is an abundant number, since it is smaller than the sum of its proper divisors (345494632).

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

218531768 is a wasteful number, since it uses less digits than its factorization.

218531768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150 (or 139 counting only the distinct ones).

The product of its digits is 80640, while the sum is 41.

The square root of 218531768 is about 14782.8200286684. The cubic root of 218531768 is about 602.3351297879.

The spelling of 218531768 in words is "two hundred eighteen million, five hundred thirty-one thousand, seven hundred sixty-eight".