217038228 has 24 divisors (see below), whose sum is σ = 552461280. Its totient is φ = 65769120.

The previous prime is 217038221. The next prime is 217038251. The reversal of 217038228 is 822830712.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217038221) 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, 821983 + ... + 822246.

It is an arithmetic number, because the mean of its divisors is an integer number (23019220).

Almost surely, 2^217038228 is an apocalyptic number.

It is an amenable number.

217038228 is an abundant number, since it is smaller than the sum of its proper divisors (335423052).

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

217038228 is a wasteful number, since it uses less digits than its factorization.

217038228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1644247 (or 1644245 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 217038228 is about 14732.2173483831. The cubic root of 217038228 is about 600.9597860880.

Subtracting from 217038228 its sum of digits (33), we obtain a triangular number (217038195 = T₂₀₈₃₄).

The spelling of 217038228 in words is "two hundred seventeen million, thirty-eight thousand, two hundred twenty-eight".