869989 has 2 divisors, whose sum is σ = 869990. Its totient is φ = 869988.

The previous prime is 869983. The next prime is 870007. The reversal of 869989 is 989968.

869989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 667489 + 202500 = 817^2 + 450^2 .

It is a cyclic number.

It is not a de Polignac number, because 869989 - 2¹³ = 861797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (869983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 434994 + 434995.

It is an arithmetic number, because the mean of its divisors is an integer number (434995).

2⁸⁶⁹⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

869989 is a deficient number, since it is larger than the sum of its proper divisors (1).

869989 is an equidigital number, since it uses as much as digits as its factorization.

869989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 49.

The square root of 869989 is about 932.7320086713. The cubic root of 869989 is about 95.4636247531.

The spelling of 869989 in words is "eight hundred sixty-nine thousand, nine hundred eighty-nine".