6991978323 has 16 divisors (see below), whose sum is σ = 10206878976. Its totient is φ = 4222259040.

The previous prime is 6991978309. The next prime is 6991978327. The reversal of 6991978323 is 3238791996.

It is not a de Polignac number, because 6991978323 - 2⁵ = 6991978291 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6991978327) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 373311 + ... + 391592.

It is an arithmetic number, because the mean of its divisors is an integer number (637929936).

Almost surely, 2^6991978323 is an apocalyptic number.

6991978323 is a deficient number, since it is larger than the sum of its proper divisors (3214900653).

6991978323 is a wasteful number, since it uses less digits than its factorization.

6991978323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765194.

The product of its digits is 4408992, while the sum is 57.

The square root of 6991978323 is about 83618.0502224251. The cubic root of 6991978323 is about 1912.2001931853.

The spelling of 6991978323 in words is "six billion, nine hundred ninety-one million, nine hundred seventy-eight thousand, three hundred twenty-three".