6663444691 has 2 divisors, whose sum is σ = 6663444692. Its totient is φ = 6663444690.

The previous prime is 6663444659. The next prime is 6663444731. The reversal of 6663444691 is 1964443666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6663444691 - 2⁵ = 6663444659 is a prime.

It is not a weakly prime, because it can be changed into another prime (6663441691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3331722345 + 3331722346.

It is an arithmetic number, because the mean of its divisors is an integer number (3331722346).

Almost surely, 2^6663444691 is an apocalyptic number.

6663444691 is a deficient number, since it is larger than the sum of its proper divisors (1).

6663444691 is an equidigital number, since it uses as much as digits as its factorization.

6663444691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 49.

The square root of 6663444691 is about 81629.9252174103. The cubic root of 6663444691 is about 1881.7688093852.

The spelling of 6663444691 in words is "six billion, six hundred sixty-three million, four hundred forty-four thousand, six hundred ninety-one".