6681963217 has 2 divisors, whose sum is σ = 6681963218. Its totient is φ = 6681963216.

The previous prime is 6681963191. The next prime is 6681963269. The reversal of 6681963217 is 7123691866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6275174656 + 406788561 = 79216^2 + 20169^2 .

It is a cyclic number.

It is not a de Polignac number, because 6681963217 - 2²⁷ = 6547745489 is a prime.

It is not a weakly prime, because it can be changed into another prime (6681966217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3340981608 + 3340981609.

It is an arithmetic number, because the mean of its divisors is an integer number (3340981609).

Almost surely, 2^6681963217 is an apocalyptic number.

It is an amenable number.

6681963217 is a deficient number, since it is larger than the sum of its proper divisors (1).

6681963217 is an equidigital number, since it uses as much as digits as its factorization.

6681963217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 49.

The square root of 6681963217 is about 81743.2762800709. The cubic root of 6681963217 is about 1883.5104187224.

The spelling of 6681963217 in words is "six billion, six hundred eighty-one million, nine hundred sixty-three thousand, two hundred seventeen".