686823955 has 4 divisors (see below), whose sum is σ = 824188752. Its totient is φ = 549459160.

The previous prime is 686823883. The next prime is 686823959. The reversal of 686823955 is 559328686.

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

It is not a de Polignac number, because 686823955 - 2¹³ = 686815763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686823959) 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, 68682391 + ... + 68682400.

It is an arithmetic number, because the mean of its divisors is an integer number (206047188).

Almost surely, 2^686823955 is an apocalyptic number.

686823955 is a deficient number, since it is larger than the sum of its proper divisors (137364797).

686823955 is a wasteful number, since it uses less digits than its factorization.

686823955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137364796.

The product of its digits is 3110400, while the sum is 52.

The square root of 686823955 is about 26207.3263611533. The cubic root of 686823955 is about 882.2976950957.

The spelling of 686823955 in words is "six hundred eighty-six million, eight hundred twenty-three thousand, nine hundred fifty-five".