685219069 has 4 divisors (see below), whose sum is σ = 686046460. Its totient is φ = 684391680.

The previous prime is 685219057. The next prime is 685219079. The reversal of 685219069 is 960912586.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 235991044 + 449228025 = 15362^2 + 21195^2 .

It is a cyclic number.

It is not a de Polignac number, because 685219069 - 2⁵ = 685219037 is a prime.

It is a super-2 number, since 2×685219069² = 939050345042453522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685219049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 412452 + ... + 414109.

It is an arithmetic number, because the mean of its divisors is an integer number (171511615).

Almost surely, 2^685219069 is an apocalyptic number.

It is an amenable number.

685219069 is a deficient number, since it is larger than the sum of its proper divisors (827391).

685219069 is an equidigital number, since it uses as much as digits as its factorization.

685219069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 827390.

The product of its (nonzero) digits is 233280, while the sum is 46.

The square root of 685219069 is about 26176.6894201692. The cubic root of 685219069 is about 881.6099441108.

It can be divided in two parts, 6852 and 19069, that added together give a square (25921 = 161²).

The spelling of 685219069 in words is "six hundred eighty-five million, two hundred nineteen thousand, sixty-nine".