1311200320 has 56 divisors (see below), whose sum is σ = 3126342744. Its totient is φ = 523800576.

The previous prime is 1311200311. The next prime is 1311200323. The reversal of 1311200320 is 230021131.

1311200320 = T₁₁₅ + T₁₁₆ + ... + T₁₉₈₈.

It can be written as a sum of positive squares in 4 ways, for example, as 8856576 + 1302343744 = 2976^2 + 36088^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1311200320.

It is not an unprimeable number, because it can be changed into a prime (1311200323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 297654 + ... + 302026.

It is an arithmetic number, because the mean of its divisors is an integer number (55827549).

Almost surely, 2^1311200320 is an apocalyptic number.

1311200320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1311200320 is an abundant number, since it is smaller than the sum of its proper divisors (1815142424).

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

1311200320 is an equidigital number, since it uses as much as digits as its factorization.

1311200320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5327 (or 5317 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 1311200320 is about 36210.5001346295. The cubic root of 1311200320 is about 1094.5182704791.

Adding to 1311200320 its reverse (230021131), we get a palindrome (1541221451).

The spelling of 1311200320 in words is "one billion, three hundred eleven million, two hundred thousand, three hundred twenty".