689631 has 16 divisors (see below), whose sum is σ = 966144. Its totient is φ = 437184.

The previous prime is 689629. The next prime is 689641. The reversal of 689631 is 136986.

It is not a de Polignac number, because 689631 - 2¹ = 689629 is a prime.

It is a super-2 number, since 2×689631² = 951181832322, which contains 22 as substring.

It is an Ulam number.

689631 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 689592 and 689601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9411 + ... + 9483.

It is an arithmetic number, because the mean of its divisors is an integer number (60384).

2⁶⁸⁹⁶³¹ is an apocalyptic number.

689631 is a deficient number, since it is larger than the sum of its proper divisors (276513).

689631 is a wasteful number, since it uses less digits than its factorization.

689631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190.

The product of its digits is 7776, while the sum is 33.

The square root of 689631 is about 830.4402446895. The cubic root of 689631 is about 88.3498042938.

The spelling of 689631 in words is "six hundred eighty-nine thousand, six hundred thirty-one".