686693649 has 8 divisors (see below), whose sum is σ = 963780640. Its totient is φ = 433701216.

The previous prime is 686693629. The next prime is 686693659. The reversal of 686693649 is 946396686.

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

It is not a de Polignac number, because 686693649 - 2¹¹ = 686691601 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57), and also a Moran number because the ratio is a prime number: 12047257 = 686693649 / (6 + 8 + 6 + 6 + 9 + 3 + 6 + 4 + 9).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (686693629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6023572 + ... + 6023685.

It is an arithmetic number, because the mean of its divisors is an integer number (120472580).

Almost surely, 2^686693649 is an apocalyptic number.

It is an amenable number.

686693649 is a deficient number, since it is larger than the sum of its proper divisors (277086991).

686693649 is a wasteful number, since it uses less digits than its factorization.

686693649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12047279.

The product of its digits is 10077696, while the sum is 57.

The square root of 686693649 is about 26204.8401826838. The cubic root of 686693649 is about 882.2418943071.

The spelling of 686693649 in words is "six hundred eighty-six million, six hundred ninety-three thousand, six hundred forty-nine".