216565164 has 60 divisors (see below), whose sum is σ = 575790600. Its totient is φ = 70958592.

The previous prime is 216565121. The next prime is 216565169. The reversal of 216565164 is 461565612.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (216565169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 13452 + ... + 24780.

It is an arithmetic number, because the mean of its divisors is an integer number (9596510).

Almost surely, 2^216565164 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216565164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287895300).

216565164 is an abundant number, since it is smaller than the sum of its proper divisors (359225436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216565164 is a wasteful number, since it uses less digits than its factorization.

216565164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11404 (or 11393 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The square root of 216565164 is about 14716.1531658243. The cubic root of 216565164 is about 600.5228442575.

The spelling of 216565164 in words is "two hundred sixteen million, five hundred sixty-five thousand, one hundred sixty-four".