685979507 has 2 divisors, whose sum is σ = 685979508. Its totient is φ = 685979506.

The previous prime is 685979471. The next prime is 685979509. The reversal of 685979507 is 705979586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685979507 - 2¹⁸ = 685717363 is a prime.

Together with 685979509, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (685979509) 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, 342989753 + 342989754.

It is an arithmetic number, because the mean of its divisors is an integer number (342989754).

Almost surely, 2^685979507 is an apocalyptic number.

685979507 is a deficient number, since it is larger than the sum of its proper divisors (1).

685979507 is an equidigital number, since it uses as much as digits as its factorization.

685979507 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4762800, while the sum is 56.

The square root of 685979507 is about 26191.2104913080. The cubic root of 685979507 is about 881.9359526750.

It can be divided in two parts, 6859 and 79507, that multiplied together give a cube (545338513 = 817³).

The spelling of 685979507 in words is "six hundred eighty-five million, nine hundred seventy-nine thousand, five hundred seven".