400440043 has 2 divisors, whose sum is σ = 400440044. Its totient is φ = 400440042.

The previous prime is 400440041. The next prime is 400440077. The reversal of 400440043 is 340044004.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 400440043 - 2¹ = 400440041 is a prime.

Together with 400440041, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 400440043.

It is not a weakly prime, because it can be changed into another prime (400440041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200220021 + 200220022.

It is an arithmetic number, because the mean of its divisors is an integer number (200220022).

Almost surely, 2^400440043 is an apocalyptic number.

400440043 is a deficient number, since it is larger than the sum of its proper divisors (1).

400440043 is an equidigital number, since it uses as much as digits as its factorization.

400440043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 19.

The square root of 400440043 is about 20010.9980510718. The cubic root of 400440043 is about 737.0763894218.

Adding to 400440043 its reverse (340044004), we get a palindrome (740484047).

The spelling of 400440043 in words is "four hundred million, four hundred forty thousand, forty-three".