687445 has 16 divisors (see below), whose sum is σ = 933120. Its totient is φ = 481600.

The previous prime is 687443. The next prime is 687457. The reversal of 687445 is 544786.

It is not a de Polignac number, because 687445 - 2¹ = 687443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 687445.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1380 + ... + 1810.

It is an arithmetic number, because the mean of its divisors is an integer number (58320).

2⁶⁸⁷⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

687445 is a deficient number, since it is larger than the sum of its proper divisors (245675).

687445 is a wasteful number, since it uses less digits than its factorization.

687445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 476.

The product of its digits is 26880, while the sum is 34.

The square root of 687445 is about 829.1230306776. The cubic root of 687445 is about 88.2563547548.

The spelling of 687445 in words is "six hundred eighty-seven thousand, four hundred forty-five".