78827779 has 2 divisors, whose sum is σ = 78827780. Its totient is φ = 78827778.

The previous prime is 78827743. The next prime is 78827803. The reversal of 78827779 is 97772887.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78827779 - 2¹¹ = 78825731 is a prime.

It is not a weakly prime, because it can be changed into another prime (78827719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39413889 + 39413890.

It is an arithmetic number, because the mean of its divisors is an integer number (39413890).

Almost surely, 2^78827779 is an apocalyptic number.

78827779 is a deficient number, since it is larger than the sum of its proper divisors (1).

78827779 is an equidigital number, since it uses as much as digits as its factorization.

78827779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2765952, while the sum is 55.

The square root of 78827779 is about 8878.5009432899. The cubic root of 78827779 is about 428.7720129682.

The spelling of 78827779 in words is "seventy-eight million, eight hundred twenty-seven thousand, seven hundred seventy-nine".