42490805081 has 2 divisors, whose sum is σ = 42490805082. Its totient is φ = 42490805080.

The previous prime is 42490805047. The next prime is 42490805117. The reversal of 42490805081 is 18050809424.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39009805081 + 3481000000 = 197509^2 + 59000^2 .

It is a cyclic number.

It is not a de Polignac number, because 42490805081 - 2¹⁸ = 42490542937 is a prime.

It is a super-2 number, since 2×42490805081² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (42490805041) 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, 21245402540 + 21245402541.

It is an arithmetic number, because the mean of its divisors is an integer number (21245402541).

Almost surely, 2^42490805081 is an apocalyptic number.

It is an amenable number.

42490805081 is a deficient number, since it is larger than the sum of its proper divisors (1).

42490805081 is an equidigital number, since it uses as much as digits as its factorization.

42490805081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 92160, while the sum is 41.

The spelling of 42490805081 in words is "forty-two billion, four hundred ninety million, eight hundred five thousand, eighty-one".