216680245 has 4 divisors (see below), whose sum is σ = 260016300. Its totient is φ = 173344192.

The previous prime is 216680221. The next prime is 216680287. The reversal of 216680245 is 542086612.

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 67864644 + 148815601 = 8238^2 + 12199^2 .

It is a cyclic number.

It is not a de Polignac number, because 216680245 - 2⁷ = 216680117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216680245.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21668020 + ... + 21668029.

It is an arithmetic number, because the mean of its divisors is an integer number (65004075).

Almost surely, 2^216680245 is an apocalyptic number.

It is an amenable number.

216680245 is a deficient number, since it is larger than the sum of its proper divisors (43336055).

216680245 is an equidigital number, since it uses as much as digits as its factorization.

216680245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43336054.

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 216680245 is about 14720.0626697035. The cubic root of 216680245 is about 600.6291964372.

The spelling of 216680245 in words is "two hundred sixteen million, six hundred eighty thousand, two hundred forty-five".