686066217 has 4 divisors (see below), whose sum is σ = 914754960. Its totient is φ = 457377476.

The previous prime is 686066203. The next prime is 686066221. The reversal of 686066217 is 712660686.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 686066217 - 2⁷ = 686066089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (686066267) 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, 114344367 + ... + 114344372.

It is an arithmetic number, because the mean of its divisors is an integer number (228688740).

Almost surely, 2^686066217 is an apocalyptic number.

It is an amenable number.

686066217 is a deficient number, since it is larger than the sum of its proper divisors (228688743).

686066217 is a wasteful number, since it uses less digits than its factorization.

686066217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228688742.

The product of its (nonzero) digits is 145152, while the sum is 42.

The square root of 686066217 is about 26192.8657653186. The cubic root of 686066217 is about 881.9731109495.

The spelling of 686066217 in words is "six hundred eighty-six million, sixty-six thousand, two hundred seventeen".