687490 has 8 divisors (see below), whose sum is σ = 1237500. Its totient is φ = 274992.

The previous prime is 687481. The next prime is 687499. The reversal of 687490 is 94786.

687490 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (687481) and next prime (687499).

It can be written as a sum of positive squares in 2 ways, for example, as 619369 + 68121 = 787^2 + 261^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (687499) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34365 + ... + 34384.

2⁶⁸⁷⁴⁹⁰ is an apocalyptic number.

687490 is a deficient number, since it is larger than the sum of its proper divisors (550010).

687490 is a wasteful number, since it uses less digits than its factorization.

687490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68756.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 687490 is about 829.1501673400. The cubic root of 687490 is about 88.2582804601.

Subtracting from 687490 its reverse (94786), we obtain a cube (592704 = 84³).

The spelling of 687490 in words is "six hundred eighty-seven thousand, four hundred ninety".