216669312 has 144 divisors (see below), whose sum is σ = 659293830. Its totient is φ = 68290560.

The previous prime is 216669287. The next prime is 216669317. The reversal of 216669312 is 213966612.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 199826496 + 16842816 = 14136^2 + 4104^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-3 number, since 3×216669312³ (a number of 26 digits) contains 333 as substring.

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

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (216669317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 415612 + ... + 416132.

Almost surely, 2^216669312 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 216669312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329646915).

216669312 is an abundant number, since it is smaller than the sum of its proper divisors (442624518).

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

216669312 is a wasteful number, since it uses less digits than its factorization.

216669312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 579 (or 545 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 216669312 is about 14719.6913011109. The cubic root of 216669312 is about 600.6190943173.

The spelling of 216669312 in words is "two hundred sixteen million, six hundred sixty-nine thousand, three hundred twelve".