216508228 has 6 divisors (see below), whose sum is σ = 378889406. Its totient is φ = 108254112.

The previous prime is 216508217. The next prime is 216508231. The reversal of 216508228 is 822805612.

It can be written as a sum of positive squares in only one way, i.e., 215737344 + 770884 = 14688^2 + 878^2 .

It is a junction number, because it is equal to n+sod(n) for n = 216508193 and 216508202.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27063525 + ... + 27063532.

Almost surely, 2^216508228 is an apocalyptic number.

It is an amenable number.

216508228 is a deficient number, since it is larger than the sum of its proper divisors (162381178).

216508228 is a wasteful number, since it uses less digits than its factorization.

216508228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54127061 (or 54127059 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 216508228 is about 14714.2185657275. The cubic root of 216508228 is about 600.4702128850.

The spelling of 216508228 in words is "two hundred sixteen million, five hundred eight thousand, two hundred twenty-eight".