2187816 has 16 divisors (see below), whose sum is σ = 5469600. Its totient is φ = 729264.

The previous prime is 2187811. The next prime is 2187817. The reversal of 2187816 is 6187812.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (2187811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45556 + ... + 45603.

It is an arithmetic number, because the mean of its divisors is an integer number (341850).

2^2187816 is an apocalyptic number.

It is an amenable number.

2187816 is an abundant number, since it is smaller than the sum of its proper divisors (3281784).

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

2187816 is a wasteful number, since it uses less digits than its factorization.

2187816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91168 (or 91164 counting only the distinct ones).

The product of its digits is 5376, while the sum is 33.

The square root of 2187816 is about 1479.1267694150. The cubic root of 2187816 is about 129.8186030192.

It can be divided in two parts, 2187 and 816, that added together give a palindrome (3003).

The spelling of 2187816 in words is "two million, one hundred eighty-seven thousand, eight hundred sixteen".