400123644409 has 2 divisors, whose sum is σ = 400123644410. Its totient is φ = 400123644408.

The previous prime is 400123644383. The next prime is 400123644413. The reversal of 400123644409 is 904446321004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 262556834409 + 137566810000 = 512403^2 + 370900^2 .

It is a cyclic number.

It is not a de Polignac number, because 400123644409 - 2⁹ = 400123643897 is a prime.

It is not a weakly prime, because it can be changed into another prime (400123644469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200061822204 + 200061822205.

It is an arithmetic number, because the mean of its divisors is an integer number (200061822205).

Almost surely, 2^400123644409 is an apocalyptic number.

It is an amenable number.

400123644409 is a deficient number, since it is larger than the sum of its proper divisors (1).

400123644409 is an equidigital number, since it uses as much as digits as its factorization.

400123644409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 82944, while the sum is 37.

The spelling of 400123644409 in words is "four hundred billion, one hundred twenty-three million, six hundred forty-four thousand, four hundred nine".