6643260581 has 8 divisors (see below), whose sum is σ = 6776308800. Its totient is φ = 6511209408.

The previous prime is 6643260563. The next prime is 6643260587. The reversal of 6643260581 is 1850623466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6643260581 - 2¹⁴ = 6643244197 is a prime.

It is a super-2 number, since 2×6643260581² = 88265822294136915122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6643260587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 235796 + ... + 262461.

It is an arithmetic number, because the mean of its divisors is an integer number (847038600).

Almost surely, 2^6643260581 is an apocalyptic number.

It is an amenable number.

6643260581 is a deficient number, since it is larger than the sum of its proper divisors (133048219).

6643260581 is a wasteful number, since it uses less digits than its factorization.

6643260581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498523.

The product of its (nonzero) digits is 207360, while the sum is 41.

The square root of 6643260581 is about 81506.1996476342. The cubic root of 6643260581 is about 1879.8668780230.

The spelling of 6643260581 in words is "six billion, six hundred forty-three million, two hundred sixty thousand, five hundred eighty-one".