1665216 has 126 divisors (see below), whose sum is σ = 5646420. Its totient is φ = 467712.

The previous prime is 1665211. The next prime is 1665221. The reversal of 1665216 is 6125661.

It is a happy number.

1665216 is a `hidden beast` number, since 1 + 6 + 652 + 1 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (1665211) and next prime (1665221).

It is a tau number, because it is divible by the number of its divisors (126).

It is a self number, because there is not a number n which added to its sum of digits gives 1665216.

It is not an unprimeable number, because it can be changed into a prime (1665211) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 28195 + ... + 28253.

2^1665216 is an apocalyptic number.

1665216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1665216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2823210).

1665216 is an abundant number, since it is smaller than the sum of its proper divisors (3981204).

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

1665216 is a wasteful number, since it uses less digits than its factorization.

1665216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91 (or 71 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 1665216 is about 1290.4324856419. The cubic root of 1665216 is about 118.5287010542.

It can be divided in two parts, 1665 and 216, that added together give a palindrome (1881).

The spelling of 1665216 in words is "one million, six hundred sixty-five thousand, two hundred sixteen".