686868537 has 4 divisors (see below), whose sum is σ = 915824720. Its totient is φ = 457912356.

The previous prime is 686868521. The next prime is 686868569. The reversal of 686868537 is 735868686.

It is a happy number.

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 686868537 - 2⁴ = 686868521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686868517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114478087 + ... + 114478092.

It is an arithmetic number, because the mean of its divisors is an integer number (228956180).

Almost surely, 2^686868537 is an apocalyptic number.

It is an amenable number.

686868537 is a deficient number, since it is larger than the sum of its proper divisors (228956183).

686868537 is a wasteful number, since it uses less digits than its factorization.

686868537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228956182.

The product of its digits is 11612160, while the sum is 57.

The square root of 686868537 is about 26208.1769110329. The cubic root of 686868537 is about 882.3167847739.

The spelling of 686868537 in words is "six hundred eighty-six million, eight hundred sixty-eight thousand, five hundred thirty-seven".