686853881 has 4 divisors (see below), whose sum is σ = 784975872. Its totient is φ = 588731892.

The previous prime is 686853877. The next prime is 686853883. The reversal of 686853881 is 188358686.

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 not a de Polignac number, because 686853881 - 2² = 686853877 is a prime.

It is a super-2 number, since 2×686853881² = 943536507689524322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686853883) 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, 49060985 + ... + 49060998.

It is an arithmetic number, because the mean of its divisors is an integer number (196243968).

Almost surely, 2^686853881 is an apocalyptic number.

It is an amenable number.

686853881 is a deficient number, since it is larger than the sum of its proper divisors (98121991).

686853881 is an equidigital number, since it uses as much as digits as its factorization.

686853881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98121990.

The product of its digits is 2211840, while the sum is 53.

The square root of 686853881 is about 26207.8973021492. The cubic root of 686853881 is about 882.3105092757.

The spelling of 686853881 in words is "six hundred eighty-six million, eight hundred fifty-three thousand, eight hundred eighty-one".