216438885 has 96 divisors (see below), whose sum is σ = 427085568. Its totient is φ = 104509440.

The previous prime is 216438857. The next prime is 216438889. The reversal of 216438885 is 588834612.

216438885 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 216438885 - 2¹⁰ = 216437861 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 216438885.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216438889) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1121349 + ... + 1121541.

It is an arithmetic number, because the mean of its divisors is an integer number (4448808).

Almost surely, 2^216438885 is an apocalyptic number.

It is an amenable number.

216438885 is a deficient number, since it is larger than the sum of its proper divisors (210646683).

216438885 is a wasteful number, since it uses less digits than its factorization.

216438885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297 (or 285 counting only the distinct ones).

The product of its digits is 368640, while the sum is 45.

The square root of 216438885 is about 14711.8620507399. The cubic root of 216438885 is about 600.4061000759.

The spelling of 216438885 in words is "two hundred sixteen million, four hundred thirty-eight thousand, eight hundred eighty-five".