686767649 has 16 divisors (see below), whose sum is σ = 760700160. Its totient is φ = 616704000.

The previous prime is 686767607. The next prime is 686767651. The reversal of 686767649 is 946767686.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-686767649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (686764649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 169649 + ... + 173649.

It is an arithmetic number, because the mean of its divisors is an integer number (47543760).

Almost surely, 2^686767649 is an apocalyptic number.

It is an amenable number.

686767649 is a deficient number, since it is larger than the sum of its proper divisors (73932511).

686767649 is a wasteful number, since it uses less digits than its factorization.

686767649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4480.

The product of its digits is 18289152, while the sum is 59.

The square root of 686767649 is about 26206.2520975434. The cubic root of 686767649 is about 882.2735841081.

The spelling of 686767649 in words is "six hundred eighty-six million, seven hundred sixty-seven thousand, six hundred forty-nine".