218345904 has 120 divisors (see below), whose sum is σ = 701955072. Its totient is φ = 62064000.

The previous prime is 218345903. The next prime is 218345957. The reversal of 218345904 is 409543812.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218345903) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 252577 + ... + 253439.

Almost surely, 2^218345904 is an apocalyptic number.

218345904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218345904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (350977536).

218345904 is an abundant number, since it is smaller than the sum of its proper divisors (483609168).

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

218345904 is a wasteful number, since it uses less digits than its factorization.

218345904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1135 (or 1126 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 218345904 is about 14776.5322048172. The cubic root of 218345904 is about 602.1643168338.

The spelling of 218345904 in words is "two hundred eighteen million, three hundred forty-five thousand, nine hundred four".