218366864 has 10 divisors (see below), whose sum is σ = 423085830. Its totient is φ = 109183424.

The previous prime is 218366851. The next prime is 218366873. The reversal of 218366864 is 468663812.

It can be written as a sum of positive squares in only one way, i.e., 114490000 + 103876864 = 10700^2 + 10192^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6823949 + ... + 6823980.

It is an arithmetic number, because the mean of its divisors is an integer number (42308583).

Almost surely, 2^218366864 is an apocalyptic number.

It is an amenable number.

218366864 is a deficient number, since it is larger than the sum of its proper divisors (204718966).

218366864 is a wasteful number, since it uses less digits than its factorization.

218366864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13647937 (or 13647931 counting only the distinct ones).

The product of its digits is 331776, while the sum is 44.

The square root of 218366864 is about 14777.2414205088. The cubic root of 218366864 is about 602.1835843661.

The spelling of 218366864 in words is "two hundred eighteen million, three hundred sixty-six thousand, eight hundred sixty-four".