218223645 has 64 divisors (see below), whose sum is σ = 395124480. Its totient is φ = 102187008.

The previous prime is 218223641. The next prime is 218223653. The reversal of 218223645 is 546322812.

It is not a de Polignac number, because 218223645 - 2² = 218223641 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218223641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 353377 + ... + 353993.

It is an arithmetic number, because the mean of its divisors is an integer number (6173820).

Almost surely, 2^218223645 is an apocalyptic number.

It is an amenable number.

218223645 is a deficient number, since it is larger than the sum of its proper divisors (176900835).

218223645 is a wasteful number, since it uses less digits than its factorization.

218223645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 734.

The product of its digits is 23040, while the sum is 33.

The square root of 218223645 is about 14772.3946941584. The cubic root of 218223645 is about 602.0519053636.

The spelling of 218223645 in words is "two hundred eighteen million, two hundred twenty-three thousand, six hundred forty-five".