2161812 has 24 divisors (see below), whose sum is σ = 5152896. Its totient is φ = 705088.

The previous prime is 2161787. The next prime is 2161813. The reversal of 2161812 is 2181612.

It is a super-2 number, since 2×2161812² = 9346862246688, which contains 22 as substring.

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 (2161813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1353 + ... + 2480.

It is an arithmetic number, because the mean of its divisors is an integer number (214704).

2^2161812 is an apocalyptic number.

It is an amenable number.

2161812 is an abundant number, since it is smaller than the sum of its proper divisors (2991084).

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

2161812 is a wasteful number, since it uses less digits than its factorization.

2161812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3887 (or 3885 counting only the distinct ones).

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

The square root of 2161812 is about 1470.3101713584. The cubic root of 2161812 is about 129.3022179254.

The spelling of 2161812 in words is "two million, one hundred sixty-one thousand, eight hundred twelve".