687743531 has 8 divisors (see below), whose sum is σ = 707447520. Its totient is φ = 668098368.

The previous prime is 687743521. The next prime is 687743533. The reversal of 687743531 is 135347786.

687743531 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 a cyclic number.

It is not a de Polignac number, because 687743531 - 2⁶ = 687743467 is a prime.

It is a super-2 number, since 2×687743531² = 945982328864695922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687743533) 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, 9575 + ... + 38303.

It is an arithmetic number, because the mean of its divisors is an integer number (88430940).

Almost surely, 2^687743531 is an apocalyptic number.

687743531 is a deficient number, since it is larger than the sum of its proper divisors (19703989).

687743531 is a wasteful number, since it uses less digits than its factorization.

687743531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29413.

The product of its digits is 423360, while the sum is 44.

The square root of 687743531 is about 26224.8647470297. The cubic root of 687743531 is about 882.6912835606.

The spelling of 687743531 in words is "six hundred eighty-seven million, seven hundred forty-three thousand, five hundred thirty-one".