2181004 has 12 divisors (see below), whose sum is σ = 4362064. Its totient is φ = 934704.

The previous prime is 2180999. The next prime is 2181007. The reversal of 2181004 is 4001812.

It is a happy number.

2181004 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (2181007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38919 + ... + 38974.

2^2181004 is an apocalyptic number.

It is an amenable number.

2181004 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2181004 is a wasteful number, since it uses less digits than its factorization.

2181004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77904 (or 77902 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 2181004 is about 1476.8222641875. The cubic root of 2181004 is about 129.6837282205.

Adding to 2181004 its reverse (4001812), we get a palindrome (6182816).

The spelling of 2181004 in words is "two million, one hundred eighty-one thousand, four".