218383947 has 6 divisors (see below), whose sum is σ = 315443492. Its totient is φ = 145589292.

The previous prime is 218383937. The next prime is 218383961. The reversal of 218383947 is 749383812.

It is not a de Polignac number, because 218383947 - 2⁴ = 218383931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218383937) 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 5 ways as a sum of consecutive naturals, for example, 12132433 + ... + 12132450.

Almost surely, 2^218383947 is an apocalyptic number.

218383947 is a deficient number, since it is larger than the sum of its proper divisors (97059545).

218383947 is a wasteful number, since it uses less digits than its factorization.

218383947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24264889 (or 24264886 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 218383947 is about 14777.8194264242. The cubic root of 218383947 is about 602.1992870445.

The spelling of 218383947 in words is "two hundred eighteen million, three hundred eighty-three thousand, nine hundred forty-seven".