6643252313 has 4 divisors (see below), whose sum is σ = 6685566180. Its totient is φ = 6600938448.

The previous prime is 6643252309. The next prime is 6643252331. The reversal of 6643252313 is 3132523466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3132523466 = 2 ⋅1566261733.

It can be written as a sum of positive squares in 2 ways, for example, as 2280253504 + 4362998809 = 47752^2 + 66053^2 .

It is a cyclic number.

It is not a de Polignac number, because 6643252313 - 2² = 6643252309 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6643252373) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21156698 + ... + 21157011.

It is an arithmetic number, because the mean of its divisors is an integer number (1671391545).

Almost surely, 2^6643252313 is an apocalyptic number.

It is an amenable number.

6643252313 is a deficient number, since it is larger than the sum of its proper divisors (42313867).

6643252313 is a wasteful number, since it uses less digits than its factorization.

6643252313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42313866.

The product of its digits is 77760, while the sum is 35.

The square root of 6643252313 is about 81506.1489275502. The cubic root of 6643252313 is about 1879.8660981476.

Adding to 6643252313 its reverse (3132523466), we get a palindrome (9775775779).

The spelling of 6643252313 in words is "six billion, six hundred forty-three million, two hundred fifty-two thousand, three hundred thirteen".