2181616 has 10 divisors (see below), whose sum is σ = 4226912. Its totient is φ = 1090800.

The previous prime is 2181611. The next prime is 2181629. The reversal of 2181616 is 6161812.

2181616 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68160 + ... + 68191.

2^2181616 is an apocalyptic number.

It is an amenable number.

2181616 is a deficient number, since it is larger than the sum of its proper divisors (2045296).

2181616 is a wasteful number, since it uses less digits than its factorization.

2181616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136359 (or 136353 counting only the distinct ones).

The product of its digits is 576, while the sum is 25.

The square root of 2181616 is about 1477.0294512974. The cubic root of 2181616 is about 129.6958570412.

The spelling of 2181616 in words is "two million, one hundred eighty-one thousand, six hundred sixteen".