686661016774 has 4 divisors (see below), whose sum is σ = 1029991525164. Its totient is φ = 343330508386.

The previous prime is 686661016763. The next prime is 686661016777. The reversal of 686661016774 is 477610166686.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686661016777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171665254192 + ... + 171665254195.

It is an arithmetic number, because the mean of its divisors is an integer number (257497881291).

Almost surely, 2^686661016774 is an apocalyptic number.

686661016774 is a deficient number, since it is larger than the sum of its proper divisors (343330508390).

686661016774 is a wasteful number, since it uses less digits than its factorization.

686661016774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343330508389.

The product of its (nonzero) digits is 12192768, while the sum is 58.

The spelling of 686661016774 in words is "six hundred eighty-six billion, six hundred sixty-one million, sixteen thousand, seven hundred seventy-four".