3999216 has 120 divisors (see below), whose sum is σ = 12253680. Its totient is φ = 1118208.

The previous prime is 3999211. The next prime is 3999239. The reversal of 3999216 is 6129993.

It is a happy number.

3999216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×3999216² = 31987457229312, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3999211) 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 23 ways as a sum of consecutive naturals, for example, 137890 + ... + 137918.

It is an arithmetic number, because the mean of its divisors is an integer number (102114).

Almost surely, 2^3999216 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 3999216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6126840).

3999216 is an abundant number, since it is smaller than the sum of its proper divisors (8254464).

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

3999216 is a wasteful number, since it uses less digits than its factorization.

3999216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83 (or 64 counting only the distinct ones).

The product of its digits is 26244, while the sum is 39.

The square root of 3999216 is about 1999.8039903951. The cubic root of 3999216 is about 158.7297334990.

The spelling of 3999216 in words is "three million, nine hundred ninety-nine thousand, two hundred sixteen".