217005812 has 24 divisors (see below), whose sum is σ = 384570816. Its totient is φ = 107137728.

The previous prime is 217005809. The next prime is 217005829. The reversal of 217005812 is 218500712.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 107888 + ... + 109880.

It is an arithmetic number, because the mean of its divisors is an integer number (16023784).

Almost surely, 2^217005812 is an apocalyptic number.

It is an amenable number.

217005812 is a deficient number, since it is larger than the sum of its proper divisors (167565004).

217005812 is a wasteful number, since it uses less digits than its factorization.

217005812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2327 (or 2325 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 217005812 is about 14731.1171334695. The cubic root of 217005812 is about 600.9298655796.

The spelling of 217005812 in words is "two hundred seventeen million, five thousand, eight hundred twelve".