686135772 has 144 divisors (see below), whose sum is σ = 2122545152. Its totient is φ = 189656640.

The previous prime is 686135753. The next prime is 686135789. The reversal of 686135772 is 277531686.

686135772 is a `hidden beast` number, since 68 + 6 + 13 + 577 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 209298 + ... + 212550.

Almost surely, 2^686135772 is an apocalyptic number.

686135772 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686135772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1061272576).

686135772 is an abundant number, since it is smaller than the sum of its proper divisors (1436409380).

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

686135772 is a wasteful number, since it uses less digits than its factorization.

686135772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3310 (or 3296 counting only the distinct ones).

The product of its digits is 423360, while the sum is 45.

The square root of 686135772 is about 26194.1934787082. The cubic root of 686135772 is about 882.0029154423.

The spelling of 686135772 in words is "six hundred eighty-six million, one hundred thirty-five thousand, seven hundred seventy-two".