687553 has 4 divisors (see below), whose sum is σ = 723760. Its totient is φ = 651348.

The previous prime is 687551. The next prime is 687559. The reversal of 687553 is 355786.

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, and also an emirpimes, since its reverse is a distinct semiprime: 355786 = 2 ⋅177893.

It is a cyclic number.

It is not a de Polignac number, because 687553 - 2¹ = 687551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18075 + ... + 18112.

It is an arithmetic number, because the mean of its divisors is an integer number (180940).

2⁶⁸⁷⁵⁵³ is an apocalyptic number.

It is an amenable number.

687553 is a deficient number, since it is larger than the sum of its proper divisors (36207).

687553 is a wasteful number, since it uses less digits than its factorization.

687553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36206.

The product of its digits is 25200, while the sum is 34.

The square root of 687553 is about 829.1881571754. The cubic root of 687553 is about 88.2609763062.

The spelling of 687553 in words is "six hundred eighty-seven thousand, five hundred fifty-three".