216385949 has 8 divisors (see below), whose sum is σ = 233606520. Its totient is φ = 199247616.

The previous prime is 216385937. The next prime is 216385957. The reversal of 216385949 is 949583612.

It can be written as a sum of positive squares in 4 ways, for example, as 1909924 + 214476025 = 1382^2 + 14645^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216385949 - 2⁸ = 216385693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216385969) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15032 + ... + 25665.

It is an arithmetic number, because the mean of its divisors is an integer number (29200815).

Almost surely, 2^216385949 is an apocalyptic number.

It is an amenable number.

216385949 is a deficient number, since it is larger than the sum of its proper divisors (17220571).

216385949 is a wasteful number, since it uses less digits than its factorization.

216385949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41119.

The product of its digits is 466560, while the sum is 47.

The square root of 216385949 is about 14710.0628482682. The cubic root of 216385949 is about 600.3571475524.

The spelling of 216385949 in words is "two hundred sixteen million, three hundred eighty-five thousand, nine hundred forty-nine".