688339777 has 2 divisors, whose sum is σ = 688339778. Its totient is φ = 688339776.

The previous prime is 688339759. The next prime is 688339781. The reversal of 688339777 is 777933886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 687698176 + 641601 = 26224^2 + 801^2 .

It is a cyclic number.

It is not a de Polignac number, because 688339777 - 2¹¹ = 688337729 is a prime.

It is not a weakly prime, because it can be changed into another prime (688339747) 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, 344169888 + 344169889.

It is an arithmetic number, because the mean of its divisors is an integer number (344169889).

Almost surely, 2^688339777 is an apocalyptic number.

It is an amenable number.

688339777 is a deficient number, since it is larger than the sum of its proper divisors (1).

688339777 is an equidigital number, since it uses as much as digits as its factorization.

688339777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10668672, while the sum is 58.

The square root of 688339777 is about 26236.2302360686. The cubic root of 688339777 is about 882.9462958351.

The spelling of 688339777 in words is "six hundred eighty-eight million, three hundred thirty-nine thousand, seven hundred seventy-seven".