686754021 has 8 divisors (see below), whose sum is σ = 917788480. Its totient is φ = 456777792.

The previous prime is 686753971. The next prime is 686754037. The reversal of 686754021 is 120457686.

686754021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 686754021 - 2⁶ = 686753957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686754091) 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, 263041 + ... + 265638.

It is an arithmetic number, because the mean of its divisors is an integer number (114723560).

Almost surely, 2^686754021 is an apocalyptic number.

It is an amenable number.

686754021 is a deficient number, since it is larger than the sum of its proper divisors (231034459).

686754021 is a wasteful number, since it uses less digits than its factorization.

686754021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529115.

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 686754021 is about 26205.9920819648. The cubic root of 686754021 is about 882.2677482168.

The spelling of 686754021 in words is "six hundred eighty-six million, seven hundred fifty-four thousand, twenty-one".