218221845 has 8 divisors (see below), whose sum is σ = 349154976. Its totient is φ = 116384976.

The previous prime is 218221841. The next prime is 218221847. The reversal of 218221845 is 548122812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 218221845 - 2² = 218221841 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218221841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7274047 + ... + 7274076.

It is an arithmetic number, because the mean of its divisors is an integer number (43644372).

Almost surely, 2^218221845 is an apocalyptic number.

It is an amenable number.

218221845 is a deficient number, since it is larger than the sum of its proper divisors (130933131).

218221845 is a wasteful number, since it uses less digits than its factorization.

218221845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14548131.

The product of its digits is 10240, while the sum is 33.

The square root of 218221845 is about 14772.3337695843. Note that the first 3 decimals coincide. The cubic root of 218221845 is about 602.0502500337.

The spelling of 218221845 in words is "two hundred eighteen million, two hundred twenty-one thousand, eight hundred forty-five".