216875021 has 8 divisors (see below), whose sum is σ = 244749600. Its totient is φ = 190360240.

The previous prime is 216875017. The next prime is 216875023. The reversal of 216875021 is 120578612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216875021 - 2² = 216875017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216875023) 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, 339611 + ... + 340248.

It is an arithmetic number, because the mean of its divisors is an integer number (30593700).

Almost surely, 2^216875021 is an apocalyptic number.

It is an amenable number.

216875021 is a deficient number, since it is larger than the sum of its proper divisors (27874579).

216875021 is a wasteful number, since it uses less digits than its factorization.

216875021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 679899.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 216875021 is about 14726.6771880150. The cubic root of 216875021 is about 600.8091130327.

The spelling of 216875021 in words is "two hundred sixteen million, eight hundred seventy-five thousand, twenty-one".