218918972 has 12 divisors (see below), whose sum is σ = 383230176. Its totient is φ = 109424640.

The previous prime is 218918971. The next prime is 218918989. The reversal of 218918972 is 279819812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218918971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9788 + ... + 23100.

It is an arithmetic number, because the mean of its divisors is an integer number (31935848).

Almost surely, 2^218918972 is an apocalyptic number.

It is an amenable number.

218918972 is a deficient number, since it is larger than the sum of its proper divisors (164311204).

218918972 is a wasteful number, since it uses less digits than its factorization.

218918972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17428 (or 17426 counting only the distinct ones).

The product of its digits is 145152, while the sum is 47.

The square root of 218918972 is about 14795.9106512577. The cubic root of 218918972 is about 602.6906676611.

The spelling of 218918972 in words is "two hundred eighteen million, nine hundred eighteen thousand, nine hundred seventy-two".