685860577 has 2 divisors, whose sum is σ = 685860578. Its totient is φ = 685860576.

The previous prime is 685860509. The next prime is 685860583. The reversal of 685860577 is 775068586.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 641558241 + 44302336 = 25329^2 + 6656^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-685860577 is a prime.

It is not a weakly prime, because it can be changed into another prime (685860377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342930288 + 342930289.

It is an arithmetic number, because the mean of its divisors is an integer number (342930289).

Almost surely, 2^685860577 is an apocalyptic number.

It is an amenable number.

685860577 is a deficient number, since it is larger than the sum of its proper divisors (1).

685860577 is an equidigital number, since it uses as much as digits as its factorization.

685860577 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2822400, while the sum is 52.

The square root of 685860577 is about 26188.9399747298. The cubic root of 685860577 is about 881.8849819079.

The spelling of 685860577 in words is "six hundred eighty-five million, eight hundred sixty thousand, five hundred seventy-seven".