864121 has 2 divisors, whose sum is σ = 864122. Its totient is φ = 864120.

The previous prime is 864119. The next prime is 864131. The reversal of 864121 is 121468.

It is the 380-th star number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 837225 + 26896 = 915^2 + 164^2 .

It is a cyclic number.

It is not a de Polignac number, because 864121 - 2¹ = 864119 is a prime.

Together with 864119, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 864092 and 864101.

It is not a weakly prime, because it can be changed into another prime (864131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432060 + 432061.

It is an arithmetic number, because the mean of its divisors is an integer number (432061).

2⁸⁶⁴¹²¹ is an apocalyptic number.

It is an amenable number.

864121 is a deficient number, since it is larger than the sum of its proper divisors (1).

864121 is an equidigital number, since it uses as much as digits as its factorization.

864121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 384, while the sum is 22.

The square root of 864121 is about 929.5810884479. The cubic root of 864121 is about 95.2485091033.

Adding to 864121 its reverse (121468), we get a palindrome (985589).

The spelling of 864121 in words is "eight hundred sixty-four thousand, one hundred twenty-one".