685737397 has 2 divisors, whose sum is σ = 685737398. Its totient is φ = 685737396.

The previous prime is 685737359. The next prime is 685737401. The reversal of 685737397 is 793737586.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 427621041 + 258116356 = 20679^2 + 16066^2 .

It is a cyclic number.

It is not a de Polignac number, because 685737397 - 2¹⁵ = 685704629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (685737307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342868698 + 342868699.

It is an arithmetic number, because the mean of its divisors is an integer number (342868699).

Almost surely, 2^685737397 is an apocalyptic number.

It is an amenable number.

685737397 is a deficient number, since it is larger than the sum of its proper divisors (1).

685737397 is an equidigital number, since it uses as much as digits as its factorization.

685737397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6667920, while the sum is 55.

The square root of 685737397 is about 26186.5881130017. The cubic root of 685737397 is about 881.8321834725.

The spelling of 685737397 in words is "six hundred eighty-five million, seven hundred thirty-seven thousand, three hundred ninety-seven".