686447172 has 36 divisors (see below), whose sum is σ = 1746845100. Its totient is φ = 227278272.

The previous prime is 686447161. The next prime is 686447183. The reversal of 686447172 is 271744686.

It is an interprime number because it is at equal distance from previous prime (686447161) and next prime (686447183).

It can be written as a sum of positive squares in 2 ways, for example, as 351337536 + 335109636 = 18744^2 + 18306^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58623 + ... + 69350.

It is an arithmetic number, because the mean of its divisors is an integer number (48523475).

Almost surely, 2^686447172 is an apocalyptic number.

It is an amenable number.

686447172 is an abundant number, since it is smaller than the sum of its proper divisors (1060397928).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686447172 is a wasteful number, since it uses less digits than its factorization.

686447172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128132 (or 128127 counting only the distinct ones).

The product of its digits is 451584, while the sum is 45.

The square root of 686447172 is about 26200.1368698715. The cubic root of 686447172 is about 882.1363264371.

The spelling of 686447172 in words is "six hundred eighty-six million, four hundred forty-seven thousand, one hundred seventy-two".