2181860 has 24 divisors (see below), whose sum is σ = 4623360. Its totient is φ = 864864.

The previous prime is 2181857. The next prime is 2181869. The reversal of 2181860 is 681812.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (2181869) 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, 2111 + ... + 2969.

It is an arithmetic number, because the mean of its divisors is an integer number (192640).

2^2181860 is an apocalyptic number.

2181860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2181860 is an abundant number, since it is smaller than the sum of its proper divisors (2441500).

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

2181860 is a wasteful number, since it uses less digits than its factorization.

2181860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 995 (or 993 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 2181860 is about 1477.1120472056. The cubic root of 2181860 is about 129.7006920823.

The spelling of 2181860 in words is "two million, one hundred eighty-one thousand, eight hundred sixty".