77768657 has 2 divisors, whose sum is σ = 77768658. Its totient is φ = 77768656.

The previous prime is 77768623. The next prime is 77768689. The reversal of 77768657 is 75686777.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76720081 + 1048576 = 8759^2 + 1024^2 .

It is a cyclic number.

It is not a de Polignac number, because 77768657 - 2¹⁰ = 77767633 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77768599 and 77768608.

It is not a weakly prime, because it can be changed into another prime (77768617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38884328 + 38884329.

It is an arithmetic number, because the mean of its divisors is an integer number (38884329).

Almost surely, 2^77768657 is an apocalyptic number.

It is an amenable number.

77768657 is a deficient number, since it is larger than the sum of its proper divisors (1).

77768657 is an equidigital number, since it uses as much as digits as its factorization.

77768657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3457440, while the sum is 53.

The square root of 77768657 is about 8818.6539222265. The cubic root of 77768657 is about 426.8430354702.

The spelling of 77768657 in words is "seventy-seven million, seven hundred sixty-eight thousand, six hundred fifty-seven".