1304820 has 72 divisors (see below), whose sum is σ = 4324320. Its totient is φ = 315840.

The previous prime is 1304803. The next prime is 1304833. The reversal of 1304820 is 284031.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 1304793 and 1304802.

It is a congruent number.

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, 1651 + ... + 2309.

It is an arithmetic number, because the mean of its divisors is an integer number (60060).

2^1304820 is an apocalyptic number.

1304820 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 1304820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2162160).

1304820 is an abundant number, since it is smaller than the sum of its proper divisors (3019500).

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

1304820 is a wasteful number, since it uses less digits than its factorization.

1304820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685 (or 680 counting only the distinct ones).

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

The square root of 1304820 is about 1142.2871793030. The cubic root of 1304820 is about 109.2740069112.

Adding to 1304820 its reverse (284031), we get a palindrome (1588851).

It can be divided in two parts, 130 and 4820, that added together give a triangular number (4950 = T₉₉).

The spelling of 1304820 in words is "one million, three hundred four thousand, eight hundred twenty".