686220389 has 16 divisors (see below), whose sum is σ = 715723008. Its totient is φ = 657372672.

The previous prime is 686220347. The next prime is 686220391. The reversal of 686220389 is 983022686.

686220389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 686220389 - 2¹⁶ = 686154853 is a prime.

It is a super-2 number, since 2×686220389² = 941796844558622642, which contains 22 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 (686220889) 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, 943544 + ... + 944270.

It is an arithmetic number, because the mean of its divisors is an integer number (44732688).

Almost surely, 2^686220389 is an apocalyptic number.

It is an amenable number.

686220389 is a deficient number, since it is larger than the sum of its proper divisors (29502619).

686220389 is a wasteful number, since it uses less digits than its factorization.

686220389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124.

The product of its (nonzero) digits is 248832, while the sum is 44.

The square root of 686220389 is about 26195.8086151201. The cubic root of 686220389 is about 882.0391713243.

The spelling of 686220389 in words is "six hundred eighty-six million, two hundred twenty thousand, three hundred eighty-nine".