1331020320 has 144 divisors (see below), whose sum is σ = 4877324928. Its totient is φ = 304227840.

The previous prime is 1331020303. The next prime is 1331020331. The reversal of 1331020320 is 230201331.

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 1331020320.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4776 + ... + 51815.

It is an arithmetic number, because the mean of its divisors is an integer number (33870312).

Almost surely, 2^1331020320 is an apocalyptic number.

1331020320 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 1331020320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2438662464).

1331020320 is an abundant number, since it is smaller than the sum of its proper divisors (3546304608).

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

1331020320 is a wasteful number, since it uses less digits than its factorization.

1331020320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56623 (or 56608 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 1331020320 is about 36483.1511796884. The cubic root of 1331020320 is about 1100.0055977677.

Adding to 1331020320 its reverse (230201331), we get a palindrome (1561221651).

The spelling of 1331020320 in words is "one billion, three hundred thirty-one million, twenty thousand, three hundred twenty".