218609090 has 24 divisors (see below), whose sum is σ = 457741692. Its totient is φ = 74951520.

The previous prime is 218609057. The next prime is 218609093. The reversal of 218609090 is 90906812.

218609090 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 201725209 + 16883881 = 14203^2 + 4109^2 .

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 218609090.

It is not an unprimeable number, because it can be changed into a prime (218609093) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 222581 + ... + 223560.

Almost surely, 2^218609090 is an apocalyptic number.

218609090 is an abundant number, since it is smaller than the sum of its proper divisors (239132602).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218609090 is a wasteful number, since it uses less digits than its factorization.

218609090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 446162 (or 446155 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 218609090 is about 14785.4350629259. The cubic root of 218609090 is about 602.4061618174.

The spelling of 218609090 in words is "two hundred eighteen million, six hundred nine thousand, ninety".