689629 has 2 divisors, whose sum is σ = 689630. Its totient is φ = 689628.

The previous prime is 689621. The next prime is 689641. The reversal of 689629 is 926986.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 688900 + 729 = 830^2 + 27^2 .

It is a cyclic number.

It is not a de Polignac number, because 689629 - 2³ = 689621 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 689591 and 689600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344814 + 344815.

It is an arithmetic number, because the mean of its divisors is an integer number (344815).

2⁶⁸⁹⁶²⁹ is an apocalyptic number.

It is an amenable number.

689629 is a deficient number, since it is larger than the sum of its proper divisors (1).

689629 is an equidigital number, since it uses as much as digits as its factorization.

689629 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 40.

The square root of 689629 is about 830.4390405081. The cubic root of 689629 is about 88.3497188859.

The spelling of 689629 in words is "six hundred eighty-nine thousand, six hundred twenty-nine".