685609471 has 4 divisors (see below), whose sum is σ = 721694200. Its totient is φ = 649524744.

The previous prime is 685609469. The next prime is 685609481. The reversal of 685609471 is 174906586.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 174906586 = 2 ⋅87453293.

It is a cyclic number.

It is not a de Polignac number, because 685609471 - 2¹ = 685609469 is a prime.

It is a super-3 number, since 3×685609471³ (a number of 27 digits) contains 333 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 (685609411) 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, 18042336 + ... + 18042373.

It is an arithmetic number, because the mean of its divisors is an integer number (180423550).

Almost surely, 2^685609471 is an apocalyptic number.

685609471 is a deficient number, since it is larger than the sum of its proper divisors (36084729).

685609471 is a wasteful number, since it uses less digits than its factorization.

685609471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36084728.

The product of its (nonzero) digits is 362880, while the sum is 46.

The square root of 685609471 is about 26184.1454128257. The cubic root of 685609471 is about 881.7773440738. Note that the first 3 decimals are identical.

The spelling of 685609471 in words is "six hundred eighty-five million, six hundred nine thousand, four hundred seventy-one".