216788105 has 4 divisors (see below), whose sum is σ = 260145732. Its totient is φ = 173430480.

The previous prime is 216788071. The next prime is 216788107. The reversal of 216788105 is 501887612.

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

It can be written as a sum of positive squares in 2 ways, for example, as 161315401 + 55472704 = 12701^2 + 7448^2 .

It is not a de Polignac number, because 216788105 - 2⁸ = 216787849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216788107) 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, 21678806 + ... + 21678815.

It is an arithmetic number, because the mean of its divisors is an integer number (65036433).

Almost surely, 2^216788105 is an apocalyptic number.

It is an amenable number.

216788105 is a deficient number, since it is larger than the sum of its proper divisors (43357627).

216788105 is an equidigital number, since it uses as much as digits as its factorization.

216788105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43357626.

The product of its (nonzero) digits is 26880, while the sum is 38.

The square root of 216788105 is about 14723.7259211111. The cubic root of 216788105 is about 600.7288411443.

The spelling of 216788105 in words is "two hundred sixteen million, seven hundred eighty-eight thousand, one hundred five".