685492490 has 8 divisors (see below), whose sum is σ = 1233886500. Its totient is φ = 274196992.

The previous prime is 685492487. The next prime is 685492499. The reversal of 685492490 is 94294586.

It can be written as a sum of positive squares in 2 ways, for example, as 659411041 + 26081449 = 25679^2 + 5107^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (685492499) 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, 34274615 + ... + 34274634.

Almost surely, 2^685492490 is an apocalyptic number.

685492490 is a deficient number, since it is larger than the sum of its proper divisors (548394010).

685492490 is a wasteful number, since it uses less digits than its factorization.

685492490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68549256.

The product of its (nonzero) digits is 622080, while the sum is 47.

The square root of 685492490 is about 26181.9115039372. The cubic root of 685492490 is about 881.7271906132.

The spelling of 685492490 in words is "six hundred eighty-five million, four hundred ninety-two thousand, four hundred ninety".