6513781264 has 15 divisors (see below), whose sum is σ = 12621076717. Its totient is φ = 3256729216.

The previous prime is 6513781259. The next prime is 6513781289. The reversal of 6513781264 is 4621873156.

The square root of 6513781264 is 80708.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 4523907600 + 1989873664 = 67260^2 + 44608^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6513781264.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 312744 + ... + 332920.

Almost surely, 2^6513781264 is an apocalyptic number.

6513781264 is the 80708-th square number.

It is an amenable number.

6513781264 is a deficient number, since it is larger than the sum of its proper divisors (6107295453).

6513781264 is an frugal number, since it uses more digits than its factorization.

6513781264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40362 (or 20179 counting only the distinct ones).

The product of its digits is 241920, while the sum is 43.

The cubic root of 6513781264 is about 1867.5735889479.

The spelling of 6513781264 in words is "six billion, five hundred thirteen million, seven hundred eighty-one thousand, two hundred sixty-four".