216887 has 4 divisors (see below), whose sum is σ = 236616. Its totient is φ = 197160.

The previous prime is 216877. The next prime is 216899. The reversal of 216887 is 788612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216887 - 2¹⁰ = 215863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9848 + ... + 9869.

It is an arithmetic number, because the mean of its divisors is an integer number (59154).

2²¹⁶⁸⁸⁷ is an apocalyptic number.

216887 is a deficient number, since it is larger than the sum of its proper divisors (19729).

216887 is a wasteful number, since it uses less digits than its factorization.

216887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19728.

The product of its digits is 5376, while the sum is 32.

The square root of 216887 is about 465.7112839518. The cubic root of 216887 is about 60.0820174641.

The spelling of 216887 in words is "two hundred sixteen thousand, eight hundred eighty-seven".