218402386 has 16 divisors (see below), whose sum is σ = 332162136. Its totient is φ = 107692416.

The previous prime is 218402381. The next prime is 218402399. The reversal of 218402386 is 683204812.

It can be written as a sum of positive squares in 4 ways, for example, as 213715161 + 4687225 = 14619^2 + 2165^2 .

It is not an unprimeable number, because it can be changed into a prime (218402381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40480 + ... + 45556.

Almost surely, 2^218402386 is an apocalyptic number.

218402386 is a deficient number, since it is larger than the sum of its proper divisors (113759750).

218402386 is a wasteful number, since it uses less digits than its factorization.

218402386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5373.

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 218402386 is about 14778.4432874373. The cubic root of 218402386 is about 602.2162352380.

The spelling of 218402386 in words is "two hundred eighteen million, four hundred two thousand, three hundred eighty-six".