686938751 has 4 divisors (see below), whose sum is σ = 698200104. Its totient is φ = 675677400.

The previous prime is 686938741. The next prime is 686938753. The reversal of 686938751 is 157839686.

It is a happy number.

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 686938751 - 2¹⁸ = 686676607 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 686938693 and 686938702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686938753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5630585 + ... + 5630706.

It is an arithmetic number, because the mean of its divisors is an integer number (174550026).

Almost surely, 2^686938751 is an apocalyptic number.

686938751 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

686938751 is a deficient number, since it is larger than the sum of its proper divisors (11261353).

686938751 is a wasteful number, since it uses less digits than its factorization.

686938751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11261352.

The product of its digits is 2177280, while the sum is 53.

The square root of 686938751 is about 26209.5164205675. The cubic root of 686938751 is about 882.3468482074.

The spelling of 686938751 in words is "six hundred eighty-six million, nine hundred thirty-eight thousand, seven hundred fifty-one".