217996028 has 12 divisors (see below), whose sum is σ = 381752952. Its totient is φ = 108923760.

The previous prime is 217996027. The next prime is 217996033. The reversal of 217996028 is 820699712.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 217996028.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217996027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11675 + ... + 23922.

It is an arithmetic number, because the mean of its divisors is an integer number (31812746).

Almost surely, 2^217996028 is an apocalyptic number.

It is an amenable number.

217996028 is a deficient number, since it is larger than the sum of its proper divisors (163756924).

217996028 is a wasteful number, since it uses less digits than its factorization.

217996028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37132 (or 37130 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 217996028 is about 14764.6885507281. The cubic root of 217996028 is about 601.8425102093.

The spelling of 217996028 in words is "two hundred seventeen million, nine hundred ninety-six thousand, twenty-eight".