400321 has 2 divisors, whose sum is σ = 400322. Its totient is φ = 400320.

The previous prime is 400313. The next prime is 400331. The reversal of 400321 is 123004.

It is an a-pointer prime, because the next prime (400331) can be obtained adding 400321 to its sum of digits (10).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 330625 + 69696 = 575^2 + 264^2 .

It is a cyclic number.

It is not a de Polignac number, because 400321 - 2³ = 400313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400298 and 400307.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200160 + 200161.

It is an arithmetic number, because the mean of its divisors is an integer number (200161).

2⁴⁰⁰³²¹ is an apocalyptic number.

It is an amenable number.

400321 is a deficient number, since it is larger than the sum of its proper divisors (1).

400321 is an equidigital number, since it uses as much as digits as its factorization.

400321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 400321 is about 632.7092539232. The cubic root of 400321 is about 73.7003342714.

Adding to 400321 its reverse (123004), we get a palindrome (523325).

The spelling of 400321 in words is "four hundred thousand, three hundred twenty-one", and thus it is an iban number.