133121 has 2 divisors, whose sum is σ = 133122. Its totient is φ = 133120.

The previous prime is 133117. The next prime is 133153. The reversal of 133121 is 121331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132496 + 625 = 364^2 + 25^2 .

It is a cyclic number.

It is not a de Polignac number, because 133121 - 2² = 133117 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (133321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66560 + 66561.

It is an arithmetic number, because the mean of its divisors is an integer number (66561).

It is a Proth number, since it is equal to 65 ⋅ 2¹¹ + 1 and 65 < 2¹¹.

2¹³³¹²¹ is an apocalyptic number.

It is an amenable number.

133121 is a deficient number, since it is larger than the sum of its proper divisors (1).

133121 is an equidigital number, since it uses as much as digits as its factorization.

133121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18, while the sum is 11.

The square root of 133121 is about 364.8575064323. The cubic root of 133121 is about 51.0601622452.

Adding to 133121 its reverse (121331), we get a palindrome (254452).

The spelling of 133121 in words is "one hundred thirty-three thousand, one hundred twenty-one".