689690 has 16 divisors (see below), whose sum is σ = 1314792. Its totient is φ = 259584.

The previous prime is 689641. The next prime is 689693. The reversal of 689690 is 96986.

It can be written as a sum of positive squares in 4 ways, for example, as 625681 + 64009 = 791^2 + 253^2 .

It is a super-2 number, since 2×689690² = 951344592200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (689693) 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, 1859 + ... + 2198.

2⁶⁸⁹⁶⁹⁰ is an apocalyptic number.

689690 is a deficient number, since it is larger than the sum of its proper divisors (625102).

689690 is a wasteful number, since it uses less digits than its factorization.

689690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4081.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 689690 is about 830.4757672563. The cubic root of 689690 is about 88.3523237522.

Subtracting from 689690 its reverse (96986), we obtain a cube (592704 = 84³).

The spelling of 689690 in words is "six hundred eighty-nine thousand, six hundred ninety".