400457728309 has 2 divisors, whose sum is σ = 400457728310. Its totient is φ = 400457728308.

The previous prime is 400457728261. The next prime is 400457728331. The reversal of 400457728309 is 903827754004.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 263120780209 + 137336948100 = 512953^2 + 370590^2 .

It is a cyclic number.

It is not a de Polignac number, because 400457728309 - 2¹⁷ = 400457597237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400457728369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200228864154 + 200228864155.

It is an arithmetic number, because the mean of its divisors is an integer number (200228864155).

Almost surely, 2^400457728309 is an apocalyptic number.

It is an amenable number.

400457728309 is a deficient number, since it is larger than the sum of its proper divisors (1).

400457728309 is an equidigital number, since it uses as much as digits as its factorization.

400457728309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1693440, while the sum is 49.

The spelling of 400457728309 in words is "four hundred billion, four hundred fifty-seven million, seven hundred twenty-eight thousand, three hundred nine".