689551 has 2 divisors, whose sum is σ = 689552. Its totient is φ = 689550.

The previous prime is 689509. The next prime is 689561. The reversal of 689551 is 155986.

689551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 689551 - 2¹⁵ = 656783 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344775 + 344776.

It is an arithmetic number, because the mean of its divisors is an integer number (344776).

2⁶⁸⁹⁵⁵¹ is an apocalyptic number.

689551 is a deficient number, since it is larger than the sum of its proper divisors (1).

689551 is an equidigital number, since it uses as much as digits as its factorization.

689551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 34.

The square root of 689551 is about 830.3920760701. The cubic root of 689551 is about 88.3463878495.

The spelling of 689551 in words is "six hundred eighty-nine thousand, five hundred fifty-one".