7678778791 has 2 divisors, whose sum is σ = 7678778792. Its totient is φ = 7678778790.

The previous prime is 7678778753. The next prime is 7678778803. The reversal of 7678778791 is 1978778767.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7678778791 - 2⁷ = 7678778663 is a prime.

It is a super-2 number, since 2×7678778791² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7678778491) 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 as a sum of consecutive naturals, namely, 3839389395 + 3839389396.

It is an arithmetic number, because the mean of its divisors is an integer number (3839389396).

Almost surely, 2^7678778791 is an apocalyptic number.

7678778791 is a deficient number, since it is larger than the sum of its proper divisors (1).

7678778791 is an equidigital number, since it uses as much as digits as its factorization.

7678778791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58084992, while the sum is 67.

The square root of 7678778791 is about 87628.6413851088. The cubic root of 7678778791 is about 1972.8650789078.

The spelling of 7678778791 in words is "seven billion, six hundred seventy-eight million, seven hundred seventy-eight thousand, seven hundred ninety-one".