1604390 has 16 divisors (see below), whose sum is σ = 2924208. Its totient is φ = 633696.

The previous prime is 1604381. The next prime is 1604399. The reversal of 1604390 is 934061.

It is an interprime number because it is at equal distance from previous prime (1604381) and next prime (1604399).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1604399) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 137 + ... + 1796.

It is an arithmetic number, because the mean of its divisors is an integer number (182763).

2^1604390 is an apocalyptic number.

1604390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1604390 is a deficient number, since it is larger than the sum of its proper divisors (1319818).

1604390 is a wasteful number, since it uses less digits than its factorization.

1604390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2023.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 1604390 is about 1266.6451752563. The cubic root of 1604390 is about 117.0675821597.

The spelling of 1604390 in words is "one million, six hundred four thousand, three hundred ninety".