216256243 has 4 divisors (see below), whose sum is σ = 247150000. Its totient is φ = 185362488.

The previous prime is 216256223. The next prime is 216256247. The reversal of 216256243 is 342652612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216256243 - 2⁹ = 216255731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216256247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15446868 + ... + 15446881.

It is an arithmetic number, because the mean of its divisors is an integer number (61787500).

Almost surely, 2^216256243 is an apocalyptic number.

216256243 is a deficient number, since it is larger than the sum of its proper divisors (30893757).

216256243 is an equidigital number, since it uses as much as digits as its factorization.

216256243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30893756.

The product of its digits is 17280, while the sum is 31.

The square root of 216256243 is about 14705.6534366889. The cubic root of 216256243 is about 600.2371682767.

The spelling of 216256243 in words is "two hundred sixteen million, two hundred fifty-six thousand, two hundred forty-three".