1604421 has 32 divisors (see below), whose sum is σ = 2929920. Its totient is φ = 844992.

The previous prime is 1604419. The next prime is 1604437. The reversal of 1604421 is 1244061.

It is not a de Polignac number, because 1604421 - 2¹ = 1604419 is a prime.

1604421 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1604394 and 1604403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1604441) 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 31 ways as a sum of consecutive naturals, for example, 2131 + ... + 2783.

It is an arithmetic number, because the mean of its divisors is an integer number (91560).

2^1604421 is an apocalyptic number.

It is an amenable number.

1604421 is a deficient number, since it is larger than the sum of its proper divisors (1325499).

1604421 is a wasteful number, since it uses less digits than its factorization.

1604421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 682 (or 676 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1604421 is about 1266.6574122469. The cubic root of 1604421 is about 117.0683361475.

Adding to 1604421 its reverse (1244061), we get a palindrome (2848482).

It can be divided in two parts, 1604 and 421, that added together give a square (2025 = 45²).

The spelling of 1604421 in words is "one million, six hundred four thousand, four hundred twenty-one".