685349969 has 4 divisors (see below), whose sum is σ = 721421040. Its totient is φ = 649278900.

The previous prime is 685349957. The next prime is 685349981. The reversal of 685349969 is 969943586.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (685349957) and next prime (685349981).

It is a cyclic number.

It is not a de Polignac number, because 685349969 - 2²⁰ = 684301393 is a prime.

It is a super-2 number, since 2×685349969² = 939409160016601922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685346969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18035507 + ... + 18035544.

It is an arithmetic number, because the mean of its divisors is an integer number (180355260).

Almost surely, 2^685349969 is an apocalyptic number.

It is an amenable number.

685349969 is a deficient number, since it is larger than the sum of its proper divisors (36071071).

685349969 is a wasteful number, since it uses less digits than its factorization.

685349969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36071070.

The product of its digits is 12597120, while the sum is 59.

The square root of 685349969 is about 26179.1896169457. The cubic root of 685349969 is about 881.6660796345. Note that the first 3 decimals are identical.

The spelling of 685349969 in words is "six hundred eighty-five million, three hundred forty-nine thousand, nine hundred sixty-nine".