686531172 has 48 divisors (see below), whose sum is σ = 1627637760. Its totient is φ = 225187872.

The previous prime is 686531143. The next prime is 686531173. The reversal of 686531172 is 271135686.

Its product of digits (60480) is a multiple of the sum of its prime factors (2520).

It is a self number, because there is not a number n which added to its sum of digits gives 686531172.

It is not an unprimeable number, because it can be changed into a prime (686531173) 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, 327913 + ... + 329999.

It is an arithmetic number, because the mean of its divisors is an integer number (33909120).

Almost surely, 2^686531172 is an apocalyptic number.

It is an amenable number.

686531172 is an abundant number, since it is smaller than the sum of its proper divisors (941106588).

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

686531172 is a wasteful number, since it uses less digits than its factorization.

686531172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2520 (or 2518 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The square root of 686531172 is about 26201.7398658944. The cubic root of 686531172 is about 882.1723070788.

The spelling of 686531172 in words is "six hundred eighty-six million, five hundred thirty-one thousand, one hundred seventy-two".