218538330 has 32 divisors (see below), whose sum is σ = 525239424. Its totient is φ = 58193856.

The previous prime is 218538311. The next prime is 218538347. The reversal of 218538330 is 33835812.

It is a junction number, because it is equal to n+sod(n) for n = 218538291 and 218538300.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17899 + ... + 27521.

It is an arithmetic number, because the mean of its divisors is an integer number (16413732).

Almost surely, 2^218538330 is an apocalyptic number.

218538330 is an abundant number, since it is smaller than the sum of its proper divisors (306701094).

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

218538330 is a wasteful number, since it uses less digits than its factorization.

218538330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10390.

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 218538330 is about 14783.0419738293. The cubic root of 218538330 is about 602.3411586345.

The spelling of 218538330 in words is "two hundred eighteen million, five hundred thirty-eight thousand, three hundred thirty".