218916393 has 8 divisors (see below), whose sum is σ = 292062048. Its totient is φ = 145857504.

The previous prime is 218916349. The next prime is 218916407. The reversal of 218916393 is 393619812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 218916393 - 2¹⁶ = 218850857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (218916193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15555 + ... + 26072.

It is an arithmetic number, because the mean of its divisors is an integer number (36507756).

Almost surely, 2^218916393 is an apocalyptic number.

It is an amenable number.

218916393 is a deficient number, since it is larger than the sum of its proper divisors (73145655).

218916393 is a wasteful number, since it uses less digits than its factorization.

218916393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43383.

The product of its digits is 69984, while the sum is 42.

The square root of 218916393 is about 14795.8234985417. The cubic root of 218916393 is about 602.6883009630.

The spelling of 218916393 in words is "two hundred eighteen million, nine hundred sixteen thousand, three hundred ninety-three".