687028 has 6 divisors (see below), whose sum is σ = 1202306. Its totient is φ = 343512.

The previous prime is 687023. The next prime is 687031. The reversal of 687028 is 820786.

It can be written as a sum of positive squares in only one way, i.e., 685584 + 1444 = 828^2 + 38^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687023) by changing a digit.

687028 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85875 + ... + 85882.

2⁶⁸⁷⁰²⁸ is an apocalyptic number.

It is an amenable number.

687028 is a deficient number, since it is larger than the sum of its proper divisors (515278).

687028 is a wasteful number, since it uses less digits than its factorization.

687028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171761 (or 171759 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 687028 is about 828.8715220105. The cubic root of 687028 is about 88.2385058874.

The spelling of 687028 in words is "six hundred eighty-seven thousand, twenty-eight".