687521065 has 16 divisors (see below), whose sum is σ = 1028603520. Its totient is φ = 428584320.

The previous prime is 687521063. The next prime is 687521077. The reversal of 687521065 is 560125786.

It is not a de Polignac number, because 687521065 - 2¹ = 687521063 is a prime.

It is not an unprimeable number, because it can be changed into a prime (687521063) 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 15 ways as a sum of consecutive naturals, for example, 892500 + ... + 893269.

It is an arithmetic number, because the mean of its divisors is an integer number (64287720).

Almost surely, 2^687521065 is an apocalyptic number.

It is an amenable number.

687521065 is a deficient number, since it is larger than the sum of its proper divisors (341082455).

687521065 is a wasteful number, since it uses less digits than its factorization.

687521065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1785792.

The product of its (nonzero) digits is 100800, while the sum is 40.

The square root of 687521065 is about 26220.6228949657. The cubic root of 687521065 is about 882.5960978955.

The spelling of 687521065 in words is "six hundred eighty-seven million, five hundred twenty-one thousand, sixty-five".