218930985 has 128 divisors (see below), whose sum is σ = 487710720. Its totient is φ = 90720000.

The previous prime is 218930983. The next prime is 218930989. The reversal of 218930985 is 589039812.

It is a happy number.

218930985 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 218930985 - 2¹ = 218930983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 218930985.

It is not an unprimeable number, because it can be changed into a prime (218930983) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 872110 + ... + 872360.

It is an arithmetic number, because the mean of its divisors is an integer number (3810240).

Almost surely, 2^218930985 is an apocalyptic number.

It is an amenable number.

218930985 is an abundant number, since it is smaller than the sum of its proper divisors (268779735).

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

218930985 is a wasteful number, since it uses less digits than its factorization.

218930985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356 (or 350 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The square root of 218930985 is about 14796.3166024521. The cubic root of 218930985 is about 602.7016915123.

The spelling of 218930985 in words is "two hundred eighteen million, nine hundred thirty thousand, nine hundred eighty-five".