686123641 has 8 divisors (see below), whose sum is σ = 784703744. Its totient is φ = 587684160.

The previous prime is 686123639. The next prime is 686123663. The reversal of 686123641 is 146321686.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 686123641 - 2¹ = 686123639 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 686123641.

It is not an unprimeable number, because it can be changed into a prime (686723641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24480 + ... + 44401.

It is an arithmetic number, because the mean of its divisors is an integer number (98087968).

Almost surely, 2^686123641 is an apocalyptic number.

It is an amenable number.

686123641 is a deficient number, since it is larger than the sum of its proper divisors (98580103).

686123641 is a wasteful number, since it uses less digits than its factorization.

686123641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70311.

The product of its digits is 41472, while the sum is 37.

The square root of 686123641 is about 26193.9619187323. The cubic root of 686123641 is about 881.9977174232.

The spelling of 686123641 in words is "six hundred eighty-six million, one hundred twenty-three thousand, six hundred forty-one".