7778078057 has 2 divisors, whose sum is σ = 7778078058. Its totient is φ = 7778078056.

The previous prime is 7778078053. The next prime is 7778078059. The reversal of 7778078057 is 7508708777.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6056574976 + 1721503081 = 77824^2 + 41491^2 .

It is a cyclic number.

It is not a de Polignac number, because 7778078057 - 2² = 7778078053 is a prime.

Together with 7778078059, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 7778077993 and 7778078011.

It is not a weakly prime, because it can be changed into another prime (7778078053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3889039028 + 3889039029.

It is an arithmetic number, because the mean of its divisors is an integer number (3889039029).

Almost surely, 2^7778078057 is an apocalyptic number.

It is an amenable number.

7778078057 is a deficient number, since it is larger than the sum of its proper divisors (1).

7778078057 is an equidigital number, since it uses as much as digits as its factorization.

7778078057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5378240, while the sum is 56.

The square root of 7778078057 is about 88193.4127755582. The cubic root of 7778078057 is about 1981.3328149205.

The spelling of 7778078057 in words is "seven billion, seven hundred seventy-eight million, seventy-eight thousand, fifty-seven".