216420243 has 16 divisors (see below), whose sum is σ = 321474720. Its totient is φ = 128588544.

The previous prime is 216420227. The next prime is 216420257. The reversal of 216420243 is 342024612.

It is not a de Polignac number, because 216420243 - 2⁴ = 216420227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216460243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94546 + ... + 96807.

It is an arithmetic number, because the mean of its divisors is an integer number (20092170).

Almost surely, 2^216420243 is an apocalyptic number.

216420243 is a deficient number, since it is larger than the sum of its proper divisors (105054477).

216420243 is a wasteful number, since it uses less digits than its factorization.

216420243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191398.

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 216420243 is about 14711.2284667189. The cubic root of 216420243 is about 600.3888618119.

Adding to 216420243 its reverse (342024612), we get a palindrome (558444855).

The spelling of 216420243 in words is "two hundred sixteen million, four hundred twenty thousand, two hundred forty-three".