1305604020 has 144 divisors (see below), whose sum is σ = 4267831680. Its totient is φ = 297351936.

The previous prime is 1305603997. The next prime is 1305604021. The reversal of 1305604020 is 204065031.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1305604021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1054842 + ... + 1056078.

It is an arithmetic number, because the mean of its divisors is an integer number (29637720).

Almost surely, 2^1305604020 is an apocalyptic number.

1305604020 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 1305604020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2133915840).

1305604020 is an abundant number, since it is smaller than the sum of its proper divisors (2962227660).

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

1305604020 is a wasteful number, since it uses less digits than its factorization.

1305604020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1622 (or 1613 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 1305604020 is about 36133.1429576781. The cubic root of 1305604020 is about 1092.9588881917.

Adding to 1305604020 its reverse (204065031), we get a palindrome (1509669051).

The spelling of 1305604020 in words is "one billion, three hundred five million, six hundred four thousand, twenty".