40638408857 has 2 divisors, whose sum is σ = 40638408858. Its totient is φ = 40638408856.

The previous prime is 40638408821. The next prime is 40638408961. The reversal of 40638408857 is 75880483604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35066682121 + 5571726736 = 187261^2 + 74644^2 .

It is a cyclic number.

It is not a de Polignac number, because 40638408857 - 2¹⁰ = 40638407833 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40638408799 and 40638408808.

It is not a weakly prime, because it can be changed into another prime (40638408757) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20319204428 + 20319204429.

It is an arithmetic number, because the mean of its divisors is an integer number (20319204429).

Almost surely, 2^40638408857 is an apocalyptic number.

It is an amenable number.

40638408857 is a deficient number, since it is larger than the sum of its proper divisors (1).

40638408857 is an equidigital number, since it uses as much as digits as its factorization.

40638408857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5160960, while the sum is 53.

The spelling of 40638408857 in words is "forty billion, six hundred thirty-eight million, four hundred eight thousand, eight hundred fifty-seven".