3681921 has 8 divisors (see below), whose sum is σ = 4918144. Its totient is φ = 2450160.

The previous prime is 3681917. The next prime is 3681947. The reversal of 3681921 is 1291863.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3681921 - 2² = 3681917 is a prime.

It is a Duffinian number.

3681921 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (3683921) 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, 2376 + ... + 3606.

It is an arithmetic number, because the mean of its divisors is an integer number (614768).

Almost surely, 2^3681921 is an apocalyptic number.

It is an amenable number.

3681921 is a deficient number, since it is larger than the sum of its proper divisors (1236223).

3681921 is a wasteful number, since it uses less digits than its factorization.

3681921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2231.

The product of its digits is 2592, while the sum is 30.

The square root of 3681921 is about 1918.8332392368. The cubic root of 3681921 is about 154.4157121338.

The spelling of 3681921 in words is "three million, six hundred eighty-one thousand, nine hundred twenty-one".