686921212 has 12 divisors (see below), whose sum is σ = 1265381320. Its totient is φ = 325383696.

The previous prime is 686921201. The next prime is 686921293. The reversal of 686921212 is 212129686.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4519143 + ... + 4519294.

Almost surely, 2^686921212 is an apocalyptic number.

It is an amenable number.

686921212 is a deficient number, since it is larger than the sum of its proper divisors (578460108).

686921212 is a wasteful number, since it uses less digits than its factorization.

686921212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9038460 (or 9038458 counting only the distinct ones).

The product of its digits is 20736, while the sum is 37.

The square root of 686921212 is about 26209.1818262227. The cubic root of 686921212 is about 882.3393387494.

The spelling of 686921212 in words is "six hundred eighty-six million, nine hundred twenty-one thousand, two hundred twelve".