689655 has 16 divisors (see below), whose sum is σ = 1152000. Its totient is φ = 351648.

The previous prime is 689641. The next prime is 689693. The reversal of 689655 is 556986.

It is not a de Polignac number, because 689655 - 2¹⁰ = 688631 is a prime.

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 655 + ... + 1344.

It is an arithmetic number, because the mean of its divisors is an integer number (72000).

2⁶⁸⁹⁶⁵⁵ is an apocalyptic number.

689655 is a deficient number, since it is larger than the sum of its proper divisors (462345).

689655 is a wasteful number, since it uses less digits than its factorization.

689655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2030.

The product of its digits is 64800, while the sum is 39.

The square root of 689655 is about 830.4546947305. The cubic root of 689655 is about 88.3508291756.

The spelling of 689655 in words is "six hundred eighty-nine thousand, six hundred fifty-five".