6687749511 has 24 divisors (see below), whose sum is σ = 9799901696. Its totient is φ = 4394062080.

The previous prime is 6687749477. The next prime is 6687749531. The reversal of 6687749511 is 1159477866.

6687749511 is a `hidden beast` number, since 6 + 6 + 87 + 7 + 49 + 511 = 666.

It is not a de Polignac number, because 6687749511 - 2⁹ = 6687748999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6687749531) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1089531 + ... + 1095651.

Almost surely, 2^6687749511 is an apocalyptic number.

6687749511 is a deficient number, since it is larger than the sum of its proper divisors (3112152185).

6687749511 is a wasteful number, since it uses less digits than its factorization.

6687749511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7863 (or 7860 counting only the distinct ones).

The product of its digits is 2540160, while the sum is 54.

The square root of 6687749511 is about 81778.6617095193. The cubic root of 6687749511 is about 1884.0539416514.

The spelling of 6687749511 in words is "six billion, six hundred eighty-seven million, seven hundred forty-nine thousand, five hundred eleven".