218138006 has 4 divisors (see below), whose sum is σ = 327207012. Its totient is φ = 109069002.

The previous prime is 218137987. The next prime is 218138023. The reversal of 218138006 is 600831812.

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

It is a self number, because there is not a number n which added to its sum of digits gives 218138006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54534500 + ... + 54534503.

It is an arithmetic number, because the mean of its divisors is an integer number (81801753).

Almost surely, 2^218138006 is an apocalyptic number.

218138006 is a deficient number, since it is larger than the sum of its proper divisors (109069006).

218138006 is a wasteful number, since it uses less digits than its factorization.

218138006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109069005.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 218138006 is about 14769.4957936959. The cubic root of 218138006 is about 601.9731392746.

Adding to 218138006 its reverse (600831812), we get a palindrome (818969818).

The spelling of 218138006 in words is "two hundred eighteen million, one hundred thirty-eight thousand, six".