40823855581 has 2 divisors, whose sum is σ = 40823855582. Its totient is φ = 40823855580.

The previous prime is 40823855561. The next prime is 40823855603. The reversal of 40823855581 is 18555832804.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25858248025 + 14965607556 = 160805^2 + 122334^2 .

It is a cyclic number.

It is not a de Polignac number, because 40823855581 - 2³³ = 32233920989 is a prime.

It is a super-2 number, since 2×40823855581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40823855561) 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, 20411927790 + 20411927791.

It is an arithmetic number, because the mean of its divisors is an integer number (20411927791).

Almost surely, 2^40823855581 is an apocalyptic number.

It is an amenable number.

40823855581 is a deficient number, since it is larger than the sum of its proper divisors (1).

40823855581 is an equidigital number, since it uses as much as digits as its factorization.

40823855581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1536000, while the sum is 49.

The spelling of 40823855581 in words is "forty billion, eight hundred twenty-three million, eight hundred fifty-five thousand, five hundred eighty-one".