685780759 has 2 divisors, whose sum is σ = 685780760. Its totient is φ = 685780758.

The previous prime is 685780747. The next prime is 685780769. The reversal of 685780759 is 957087586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685780759 - 2⁹ = 685780247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (685780769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342890379 + 342890380.

It is an arithmetic number, because the mean of its divisors is an integer number (342890380).

Almost surely, 2^685780759 is an apocalyptic number.

685780759 is a deficient number, since it is larger than the sum of its proper divisors (1).

685780759 is an equidigital number, since it uses as much as digits as its factorization.

685780759 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4233600, while the sum is 55.

The square root of 685780759 is about 26187.4160428248. The cubic root of 685780759 is about 881.8507703744.

It can be divided in two parts, 6857 and 80759, that added together give a square (87616 = 296²).

The spelling of 685780759 in words is "six hundred eighty-five million, seven hundred eighty thousand, seven hundred fifty-nine".