217078368 has 144 divisors (see below), whose sum is σ = 637601328. Its totient is φ = 64281600.

The previous prime is 217078357. The next prime is 217078447. The reversal of 217078368 is 863870712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1199238 + ... + 1199418.

It is an arithmetic number, because the mean of its divisors is an integer number (4427787).

Almost surely, 2^217078368 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217078368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318800664).

217078368 is an abundant number, since it is smaller than the sum of its proper divisors (420522960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217078368 is a wasteful number, since it uses less digits than its factorization.

217078368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 42.

The square root of 217078368 is about 14733.5796057849. The cubic root of 217078368 is about 600.9968318488.

The spelling of 217078368 in words is "two hundred seventeen million, seventy-eight thousand, three hundred sixty-eight".