1304640 has 112 divisors (see below), whose sum is σ = 4632960. Its totient is φ = 345600.

The previous prime is 1304627. The next prime is 1304659. The reversal of 1304640 is 464031.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8565 + ... + 8715.

2^1304640 is an apocalyptic number.

1304640 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 1304640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2316480).

1304640 is an abundant number, since it is smaller than the sum of its proper divisors (3328320).

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

1304640 is a wasteful number, since it uses less digits than its factorization.

1304640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 1304640 is about 1142.2083872919. The cubic root of 1304640 is about 109.2689818948.

Adding to 1304640 its reverse (464031), we get a palindrome (1768671).

The spelling of 1304640 in words is "one million, three hundred four thousand, six hundred forty".