6778989657 has 32 divisors (see below), whose sum is σ = 10964016000. Its totient is φ = 4105451520.

The previous prime is 6778989631. The next prime is 6778989661. The reversal of 6778989657 is 7569898776.

It is not a de Polignac number, because 6778989657 - 2⁸ = 6778989401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6778989457) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 434569 + ... + 449897.

It is an arithmetic number, because the mean of its divisors is an integer number (342625500).

Almost surely, 2^6778989657 is an apocalyptic number.

It is an amenable number.

6778989657 is a deficient number, since it is larger than the sum of its proper divisors (4185026343).

6778989657 is a wasteful number, since it uses less digits than its factorization.

6778989657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16838 (or 16832 counting only the distinct ones).

The product of its digits is 320060160, while the sum is 72.

The square root of 6778989657 is about 82334.6200392034. The cubic root of 6778989657 is about 1892.5832426345.

The spelling of 6778989657 in words is "six billion, seven hundred seventy-eight million, nine hundred eighty-nine thousand, six hundred fifty-seven".