216778383 has 16 divisors (see below), whose sum is σ = 322007040. Its totient is φ = 144134712.

The previous prime is 216778379. The next prime is 216778411. The reversal of 216778383 is 383877612.

It is not a de Polignac number, because 216778383 - 2² = 216778379 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216778343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141 + ... + 20822.

It is an arithmetic number, because the mean of its divisors is an integer number (20125440).

Almost surely, 2^216778383 is an apocalyptic number.

216778383 is a deficient number, since it is larger than the sum of its proper divisors (105228657).

216778383 is a wasteful number, since it uses less digits than its factorization.

216778383 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21355 (or 21349 counting only the distinct ones).

The product of its digits is 338688, while the sum is 45.

The square root of 216778383 is about 14723.3957699982. The cubic root of 216778383 is about 600.7198609882.

The spelling of 216778383 in words is "two hundred sixteen million, seven hundred seventy-eight thousand, three hundred eighty-three".