686747771 has 4 divisors (see below), whose sum is σ = 686850000. Its totient is φ = 686645544.

The previous prime is 686747767. The next prime is 686747779. The reversal of 686747771 is 177747686.

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 686747771 - 2² = 686747767 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686747779) 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, 40271 + ... + 54728.

It is an arithmetic number, because the mean of its divisors is an integer number (171712500).

Almost surely, 2^686747771 is an apocalyptic number.

686747771 is a deficient number, since it is larger than the sum of its proper divisors (102229).

686747771 is an equidigital number, since it uses as much as digits as its factorization.

686747771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102228.

The product of its digits is 2765952, while the sum is 53.

The square root of 686747771 is about 26205.8728341569. The cubic root of 686747771 is about 882.2650717660.

The spelling of 686747771 in words is "six hundred eighty-six million, seven hundred forty-seven thousand, seven hundred seventy-one".