1604581 has 12 divisors (see below), whose sum is σ = 1795500. Its totient is φ = 1432640.

The previous prime is 1604573. The next prime is 1604593. The reversal of 1604581 is 1854061.

It can be written as a sum of positive squares in 2 ways, for example, as 245025 + 1359556 = 495^2 + 1166^2 .

It is not a de Polignac number, because 1604581 - 2³ = 1604573 is a prime.

It is a super-2 number, since 2×1604581² = 5149360371122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1604501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10695 + ... + 10843.

It is an arithmetic number, because the mean of its divisors is an integer number (149625).

2^1604581 is an apocalyptic number.

1604581 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1604581 is a deficient number, since it is larger than the sum of its proper divisors (190919).

1604581 is a wasteful number, since it uses less digits than its factorization.

1604581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 1604581 is about 1266.7205690285. The cubic root of 1604581 is about 117.0722275433.

The spelling of 1604581 in words is "one million, six hundred four thousand, five hundred eighty-one".