216355523 has 4 divisors (see below), whose sum is σ = 220958880. Its totient is φ = 211752168.

The previous prime is 216355511. The next prime is 216355543. The reversal of 216355523 is 325553612.

216355523 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 216355523 - 2⁴ = 216355507 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216355523.

It is not an unprimeable number, because it can be changed into a prime (216355543) 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, 2301608 + ... + 2301701.

It is an arithmetic number, because the mean of its divisors is an integer number (55239720).

Almost surely, 2^216355523 is an apocalyptic number.

216355523 is a deficient number, since it is larger than the sum of its proper divisors (4603357).

216355523 is an equidigital number, since it uses as much as digits as its factorization.

216355523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4603356.

The product of its digits is 27000, while the sum is 32.

The square root of 216355523 is about 14709.0286219043. The cubic root of 216355523 is about 600.3290075201.

The spelling of 216355523 in words is "two hundred sixteen million, three hundred fifty-five thousand, five hundred twenty-three".