1604644 has 6 divisors (see below), whose sum is σ = 2808134. Its totient is φ = 802320.

The previous prime is 1604621. The next prime is 1604651. The reversal of 1604644 is 4464061.

It can be written as a sum of positive squares in only one way, i.e., 1166400 + 438244 = 1080^2 + 662^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200577 + ... + 200584.

2^1604644 is an apocalyptic number.

It is an amenable number.

1604644 is a deficient number, since it is larger than the sum of its proper divisors (1203490).

1604644 is a wasteful number, since it uses less digits than its factorization.

1604644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401165 (or 401163 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 1604644 is about 1266.7454361473. The cubic root of 1604644 is about 117.0737597094.

The spelling of 1604644 in words is "one million, six hundred four thousand, six hundred forty-four".