3921664 has 18 divisors (see below), whose sum is σ = 7828520. Its totient is φ = 1960704.

The previous prime is 3921649. The next prime is 3921677. The reversal of 3921664 is 4661293.

3921664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7404 + ... + 7915.

Almost surely, 2^3921664 is an apocalyptic number.

It is an amenable number.

3921664 is a deficient number, since it is larger than the sum of its proper divisors (3906856).

3921664 is an equidigital number, since it uses as much as digits as its factorization.

3921664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15335 (or 15321 counting only the distinct ones).

The product of its digits is 7776, while the sum is 31.

The square root of 3921664 is about 1980.3191661952. The cubic root of 3921664 is about 157.6970105402.

The spelling of 3921664 in words is "three million, nine hundred twenty-one thousand, six hundred sixty-four".