216243020 has 96 divisors (see below), whose sum is σ = 538344576. Its totient is φ = 71424000.

The previous prime is 216243019. The next prime is 216243031. The reversal of 216243020 is 20342612.

It is a super-2 number, since 2×216243020² = 93522087397440800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 216242983 and 216243001.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 579554 + ... + 579926.

It is an arithmetic number, because the mean of its divisors is an integer number (5607756).

Almost surely, 2^216243020 is an apocalyptic number.

216243020 is a gapful number since it is divisible by the number (20) 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 216243020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (269172288).

216243020 is an abundant number, since it is smaller than the sum of its proper divisors (322101556).

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

216243020 is a wasteful number, since it uses less digits than its factorization.

216243020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 216243020 is about 14705.2038408177. The cubic root of 216243020 is about 600.2249341823.

Adding to 216243020 its reverse (20342612), we get a palindrome (236585632).

The spelling of 216243020 in words is "two hundred sixteen million, two hundred forty-three thousand, twenty".