218515242 has 16 divisors (see below), whose sum is σ = 476760672. Its totient is φ = 66216720.

The previous prime is 218515223. The next prime is 218515259. The reversal of 218515242 is 242515812.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1655353 + ... + 1655484.

It is an arithmetic number, because the mean of its divisors is an integer number (29797542).

Almost surely, 2^218515242 is an apocalyptic number.

218515242 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

218515242 is an abundant number, since it is smaller than the sum of its proper divisors (258245430).

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

218515242 is a wasteful number, since it uses less digits than its factorization.

218515242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3310853.

The product of its digits is 6400, while the sum is 30.

The square root of 218515242 is about 14782.2610584443. The cubic root of 218515242 is about 602.3199459676.

The spelling of 218515242 in words is "two hundred eighteen million, five hundred fifteen thousand, two hundred forty-two".