400404223993 has 2 divisors, whose sum is σ = 400404223994. Its totient is φ = 400404223992.

The previous prime is 400404223981. The next prime is 400404224081. The reversal of 400404223993 is 399322404004.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 382458138624 + 17946085369 = 618432^2 + 133963^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400404223993 is a prime.

It is not a weakly prime, because it can be changed into another prime (400404223903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200202111996 + 200202111997.

It is an arithmetic number, because the mean of its divisors is an integer number (200202111997).

Almost surely, 2^400404223993 is an apocalyptic number.

It is an amenable number.

400404223993 is a deficient number, since it is larger than the sum of its proper divisors (1).

400404223993 is an equidigital number, since it uses as much as digits as its factorization.

400404223993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 40.

Adding to 400404223993 its reverse (399322404004), we get a palindrome (799726627997).

The spelling of 400404223993 in words is "four hundred billion, four hundred four million, two hundred twenty-three thousand, nine hundred ninety-three".