400243 has 2 divisors, whose sum is σ = 400244. Its totient is φ = 400242.

The previous prime is 400237. The next prime is 400247. The reversal of 400243 is 342004.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 400243 - 2⁹ = 399731 is a prime.

It is not a weakly prime, because it can be changed into another prime (400247) 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, 200121 + 200122.

It is an arithmetic number, because the mean of its divisors is an integer number (200122).

2⁴⁰⁰²⁴³ is an apocalyptic number.

400243 is a deficient number, since it is larger than the sum of its proper divisors (1).

400243 is an equidigital number, since it uses as much as digits as its factorization.

400243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 13.

The square root of 400243 is about 632.6476112339. The cubic root of 400243 is about 73.6955472800.

Adding to 400243 its reverse (342004), we get a palindrome (742247).

The spelling of 400243 in words is "four hundred thousand, two hundred forty-three", and thus it is an iban number.