686651801 has 4 divisors (see below), whose sum is σ = 749074704. Its totient is φ = 624228900.

The previous prime is 686651759. The next prime is 686651851. The reversal of 686651801 is 108156686.

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 a cyclic number.

It is not a de Polignac number, because 686651801 - 2⁶ = 686651737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686651851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31211435 + ... + 31211456.

It is an arithmetic number, because the mean of its divisors is an integer number (187268676).

Almost surely, 2^686651801 is an apocalyptic number.

It is an amenable number.

686651801 is a deficient number, since it is larger than the sum of its proper divisors (62422903).

686651801 is a wasteful number, since it uses less digits than its factorization.

686651801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62422902.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 686651801 is about 26204.0416920749. The cubic root of 686651801 is about 882.2239722886.

The spelling of 686651801 in words is "six hundred eighty-six million, six hundred fifty-one thousand, eight hundred one".