2121816 has 32 divisors (see below), whose sum is σ = 5342400. Its totient is φ = 702240.

The previous prime is 2121809. The next prime is 2121829. The reversal of 2121816 is 6181212.

2121816 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

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

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

It is a junction number, because it is equal to n+sod(n) for n = 2121792 and 2121801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4855 + ... + 5273.

It is an arithmetic number, because the mean of its divisors is an integer number (166950).

2^2121816 is an apocalyptic number.

It is an amenable number.

2121816 is an abundant number, since it is smaller than the sum of its proper divisors (3220584).

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

2121816 is a wasteful number, since it uses less digits than its factorization.

2121816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 639 (or 635 counting only the distinct ones).

The product of its digits is 192, while the sum is 21.

The square root of 2121816 is about 1456.6454613254. The cubic root of 2121816 is about 128.4998359801.

The spelling of 2121816 in words is "two million, one hundred twenty-one thousand, eight hundred sixteen".