2129689 has 2 divisors, whose sum is σ = 2129690. Its totient is φ = 2129688.

The previous prime is 2129671. The next prime is 2129713. The reversal of 2129689 is 9869212.

2129689 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., 1334025 + 795664 = 1155^2 + 892^2 .

It is a cyclic number.

It is not a de Polignac number, because 2129689 - 2⁹ = 2129177 is a prime.

It is not a weakly prime, because it can be changed into another prime (2129389) 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, 1064844 + 1064845.

It is an arithmetic number, because the mean of its divisors is an integer number (1064845).

2^2129689 is an apocalyptic number.

It is an amenable number.

2129689 is a deficient number, since it is larger than the sum of its proper divisors (1).

2129689 is an equidigital number, since it uses as much as digits as its factorization.

2129689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 37.

The square root of 2129689 is about 1459.3454011988. The cubic root of 2129689 is about 128.6585727262.

The spelling of 2129689 in words is "two million, one hundred twenty-nine thousand, six hundred eighty-nine".