6686743491 has 6 divisors (see below), whose sum is σ = 9658629500. Its totient is φ = 4457828988.

The previous prime is 6686743487. The next prime is 6686743523. The reversal of 6686743491 is 1943476866.

6686743491 is a `hidden beast` number, since 6 + 6 + 86 + 74 + 3 + 491 = 666.

It is not a de Polignac number, because 6686743491 - 2² = 6686743487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6686743291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 371485741 + ... + 371485758.

Almost surely, 2^6686743491 is an apocalyptic number.

6686743491 is a deficient number, since it is larger than the sum of its proper divisors (2971886009).

6686743491 is a wasteful number, since it uses less digits than its factorization.

6686743491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742971505 (or 742971502 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 54.

The square root of 6686743491 is about 81772.5106071716. The cubic root of 6686743491 is about 1883.9594658744.

The spelling of 6686743491 in words is "six billion, six hundred eighty-six million, seven hundred forty-three thousand, four hundred ninety-one".