1604400 has 120 divisors (see below), whose sum is σ = 5904384. Its totient is φ = 364800.

The previous prime is 1604399. The next prime is 1604413. The reversal of 1604400 is 44061.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1604400.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8305 + ... + 8495.

2^1604400 is an apocalyptic number.

1604400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1604400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2952192).

1604400 is an abundant number, since it is smaller than the sum of its proper divisors (4299984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1604400 is a wasteful number, since it uses less digits than its factorization.

1604400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 1604400 is about 1266.6491226855. The cubic root of 1604400 is about 117.0678253826.

Adding to 1604400 its reverse (44061), we get a palindrome (1648461).

It can be divided in two parts, 160 and 4400, that added together give a triangular number (4560 = T₉₅).

The spelling of 1604400 in words is "one million, six hundred four thousand, four hundred".