689988 has 24 divisors (see below), whose sum is σ = 1734208. Its totient is φ = 212256.

The previous prime is 689987. The next prime is 690037. The reversal of 689988 is 889986.

It is a nialpdrome in base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 689988.

It is not an unprimeable number, because it can be changed into a prime (689981) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2056 + ... + 2367.

2⁶⁸⁹⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

689988 is an abundant number, since it is smaller than the sum of its proper divisors (1044220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

689988 is a wasteful number, since it uses less digits than its factorization.

689988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4443 (or 4441 counting only the distinct ones).

The product of its digits is 248832, while the sum is 48.

The square root of 689988 is about 830.6551631092. The cubic root of 689988 is about 88.3650469570.

It can be divided in two parts, 68998 and 8, that added together give a triangular number (69006 = T₃₇₁).

The spelling of 689988 in words is "six hundred eighty-nine thousand, nine hundred eighty-eight".