218538398 has 16 divisors (see below), whose sum is σ = 359686656. Its totient is φ = 98960160.

The previous prime is 218538377. The next prime is 218538401. The reversal of 218538398 is 893835812.

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 7 ways as a sum of consecutive naturals, for example, 77918 + ... + 80673.

It is an arithmetic number, because the mean of its divisors is an integer number (22480416).

Almost surely, 2^218538398 is an apocalyptic number.

218538398 is a deficient number, since it is larger than the sum of its proper divisors (141148258).

218538398 is a wasteful number, since it uses less digits than its factorization.

218538398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158659.

The product of its digits is 414720, while the sum is 47.

The square root of 218538398 is about 14783.0442737617. The cubic root of 218538398 is about 602.3412211090.

The spelling of 218538398 in words is "two hundred eighteen million, five hundred thirty-eight thousand, three hundred ninety-eight".