40243346821 has 2 divisors, whose sum is σ = 40243346822. Its totient is φ = 40243346820.

The previous prime is 40243346797. The next prime is 40243346863. The reversal of 40243346821 is 12864334204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37573557921 + 2669788900 = 193839^2 + 51670^2 .

It is a cyclic number.

It is not a de Polignac number, because 40243346821 - 2⁹ = 40243346309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40243346021) 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, 20121673410 + 20121673411.

It is an arithmetic number, because the mean of its divisors is an integer number (20121673411).

Almost surely, 2^40243346821 is an apocalyptic number.

It is an amenable number.

40243346821 is a deficient number, since it is larger than the sum of its proper divisors (1).

40243346821 is an equidigital number, since it uses as much as digits as its factorization.

40243346821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 110592, while the sum is 37.

The spelling of 40243346821 in words is "forty billion, two hundred forty-three million, three hundred forty-six thousand, eight hundred twenty-one".