2181632 has 20 divisors (see below), whose sum is σ = 4360026. Its totient is φ = 1090560.

The previous prime is 2181629. The next prime is 2181649. The reversal of 2181632 is 2361812.

It can be written as a sum of positive squares in only one way, i.e., 1290496 + 891136 = 1136^2 + 944^2 .

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 = 2181598 and 2181607.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1619 + ... + 2642.

2^2181632 is an apocalyptic number.

It is an amenable number.

2181632 is a deficient number, since it is larger than the sum of its proper divisors (2178394).

2181632 is an frugal number, since it uses more digits than its factorization.

2181632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4279 (or 4263 counting only the distinct ones).

The product of its digits is 576, while the sum is 23.

The square root of 2181632 is about 1477.0348675641. The cubic root of 2181632 is about 129.6961741041.

The spelling of 2181632 in words is "two million, one hundred eighty-one thousand, six hundred thirty-two".