218730 has 32 divisors (see below), whose sum is σ = 549504. Its totient is φ = 55616.

The previous prime is 218723. The next prime is 218737. The reversal of 218730 is 37812.

It is an interprime number because it is at equal distance from previous prime (218723) and next prime (218737).

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 218697 and 218706.

It is not an unprimeable number, because it can be changed into a prime (218737) by changing a digit.

218730 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 532 + ... + 848.

It is an arithmetic number, because the mean of its divisors is an integer number (17172).

2²¹⁸⁷³⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274752).

218730 is an abundant number, since it is smaller than the sum of its proper divisors (330774).

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

218730 is a wasteful number, since it uses less digits than its factorization.

218730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 218730 is about 467.6857919587. The cubic root of 218730 is about 60.2517202495.

The spelling of 218730 in words is "two hundred eighteen thousand, seven hundred thirty".