43240279844581 has 2 divisors, whose sum is σ = 43240279844582. Its totient is φ = 43240279844580.

The previous prime is 43240279844563. The next prime is 43240279844711. The reversal of 43240279844581 is 18544897204234.

It is a happy number.

43240279844581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31651763480100 + 11588516364481 = 5625990^2 + 3404191^2 .

It is a cyclic number.

It is not a de Polignac number, because 43240279844581 - 2¹¹ = 43240279842533 is a prime.

It is a super-2 number, since 2×43240279844581² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43240279854581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21620139922290 + 21620139922291.

It is an arithmetic number, because the mean of its divisors is an integer number (21620139922291).

Almost surely, 2^{43240279844581} is an apocalyptic number.

It is an amenable number.

43240279844581 is a deficient number, since it is larger than the sum of its proper divisors (1).

43240279844581 is an equidigital number, since it uses as much as digits as its factorization.

43240279844581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61931520, while the sum is 61.

The spelling of 43240279844581 in words is "forty-three trillion, two hundred forty billion, two hundred seventy-nine million, eight hundred forty-four thousand, five hundred eighty-one".