6866597991 has 32 divisors (see below), whose sum is σ = 10406486016. Its totient is φ = 3989628000.

The previous prime is 6866597977. The next prime is 6866597999. The reversal of 6866597991 is 1997956686.

It is a happy number.

It is not a de Polignac number, because 6866597991 - 2¹¹ = 6866595943 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6866597999) 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 31 ways as a sum of consecutive naturals, for example, 78096 + ... + 140826.

It is an arithmetic number, because the mean of its divisors is an integer number (325202688).

Almost surely, 2^6866597991 is an apocalyptic number.

6866597991 is a deficient number, since it is larger than the sum of its proper divisors (3539888025).

6866597991 is a wasteful number, since it uses less digits than its factorization.

6866597991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62883.

The product of its digits is 44089920, while the sum is 66.

The square root of 6866597991 is about 82864.9382489361. The cubic root of 6866597991 is about 1900.7013099900.

The spelling of 6866597991 in words is "six billion, eight hundred sixty-six million, five hundred ninety-seven thousand, nine hundred ninety-one".