218921359 has 4 divisors (see below), whose sum is σ = 231799104. Its totient is φ = 206043616.

The previous prime is 218921333. The next prime is 218921369. The reversal of 218921359 is 953129812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 218921359 - 2⁷ = 218921231 is a prime.

It is a super-2 number, since 2×218921359² = 95853122852813762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218921309) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6438847 + ... + 6438880.

It is an arithmetic number, because the mean of its divisors is an integer number (57949776).

Almost surely, 2^218921359 is an apocalyptic number.

218921359 is a deficient number, since it is larger than the sum of its proper divisors (12877745).

218921359 is a wasteful number, since it uses less digits than its factorization.

218921359 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12877744.

The product of its digits is 38880, while the sum is 40.

The square root of 218921359 is about 14795.9913152178. The cubic root of 218921359 is about 602.6928581479.

The spelling of 218921359 in words is "two hundred eighteen million, nine hundred twenty-one thousand, three hundred fifty-nine".