6501311321 has 4 divisors (see below), whose sum is σ = 6725494500. Its totient is φ = 6277128144.

The previous prime is 6501311317. The next prime is 6501311359. The reversal of 6501311321 is 1231131056.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3245011225 + 3256300096 = 56965^2 + 57064^2 .

It is a cyclic number.

It is not a de Polignac number, because 6501311321 - 2² = 6501311317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6501311021) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 112091546 + ... + 112091603.

It is an arithmetic number, because the mean of its divisors is an integer number (1681373625).

Almost surely, 2^6501311321 is an apocalyptic number.

It is an amenable number.

6501311321 is a deficient number, since it is larger than the sum of its proper divisors (224183179).

6501311321 is a wasteful number, since it uses less digits than its factorization.

6501311321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224183178.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 6501311321 is about 80630.7095404722. The cubic root of 6501311321 is about 1866.3810704896.

Adding to 6501311321 its reverse (1231131056), we get a palindrome (7732442377).

The spelling of 6501311321 in words is "six billion, five hundred one million, three hundred eleven thousand, three hundred twenty-one".