218865042 has 54 divisors (see below), whose sum is σ = 522885909. Its totient is φ = 66113520.

The previous prime is 218864993. The next prime is 218865083. The reversal of 218865042 is 240568812.

218865042 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 2 ways, for example, as 159744321 + 59120721 = 12639^2 + 7689^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=10461.

It is a junction number, because it is equal to n+sod(n) for n = 218864988 and 218865006.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 690268 + ... + 690584.

Almost surely, 2^218865042 is an apocalyptic number.

218865042 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 218865042

218865042 is an abundant number, since it is smaller than the sum of its proper divisors (304020867).

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

218865042 is a wasteful number, since it uses less digits than its factorization.

218865042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 664 (or 333 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 218865042 is about 14794.0880759849. The cubic root of 218865042 is about 602.6411732800.

The spelling of 218865042 in words is "two hundred eighteen million, eight hundred sixty-five thousand, forty-two".