218568890 has 8 divisors (see below), whose sum is σ = 393424020. Its totient is φ = 87427552.

The previous prime is 218568887. The next prime is 218568901. The reversal of 218568890 is 98865812.

It can be written as a sum of positive squares in 2 ways, for example, as 193237801 + 25331089 = 13901^2 + 5033^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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 3 ways as a sum of consecutive naturals, for example, 10928435 + ... + 10928454.

Almost surely, 2^218568890 is an apocalyptic number.

218568890 is a deficient number, since it is larger than the sum of its proper divisors (174855130).

218568890 is a wasteful number, since it uses less digits than its factorization.

218568890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21856896.

The product of its (nonzero) digits is 276480, while the sum is 47.

The square root of 218568890 is about 14784.0755544606. The cubic root of 218568890 is about 602.3692340876.

The spelling of 218568890 in words is "two hundred eighteen million, five hundred sixty-eight thousand, eight hundred ninety".