218909842 has 8 divisors (see below), whose sum is σ = 328441932. Its totient is φ = 109429200.

The previous prime is 218909809. The next prime is 218909857. The reversal of 218909842 is 248909812.

It can be written as a sum of positive squares in 2 ways, for example, as 218773681 + 136161 = 14791^2 + 369^2 .

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 (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 592 + ... + 20932.

Almost surely, 2^218909842 is an apocalyptic number.

218909842 is a deficient number, since it is larger than the sum of its proper divisors (109532090).

218909842 is a wasteful number, since it uses less digits than its factorization.

218909842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25724.

The product of its (nonzero) digits is 82944, while the sum is 43.

The square root of 218909842 is about 14795.6021168454. The cubic root of 218909842 is about 602.6822891543.

The spelling of 218909842 in words is "two hundred eighteen million, nine hundred nine thousand, eight hundred forty-two".