686384071 has 4 divisors (see below), whose sum is σ = 686778712. Its totient is φ = 685989432.

The previous prime is 686384059. The next prime is 686384087. The reversal of 686384071 is 170483686.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 686384071 - 2¹¹ = 686382023 is a prime.

It is a super-2 number, since 2×686384071² = 942246185845066082, 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 (686384011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194700 + ... + 198193.

It is an arithmetic number, because the mean of its divisors is an integer number (171694678).

Almost surely, 2^686384071 is an apocalyptic number.

686384071 is a deficient number, since it is larger than the sum of its proper divisors (394641).

686384071 is a wasteful number, since it uses less digits than its factorization.

686384071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394640.

The product of its (nonzero) digits is 193536, while the sum is 43.

The square root of 686384071 is about 26198.9326309298. The cubic root of 686384071 is about 882.1092957627.

The spelling of 686384071 in words is "six hundred eighty-six million, three hundred eighty-four thousand, seventy-one".