43241251981 has 2 divisors, whose sum is σ = 43241251982. Its totient is φ = 43241251980.

The previous prime is 43241251967. The next prime is 43241252027. The reversal of 43241251981 is 18915214234.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42752178756 + 489073225 = 206766^2 + 22115^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43241251981 is a prime.

It is a super-2 number, since 2×43241251981² (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 (43241251951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21620625990 + 21620625991.

It is an arithmetic number, because the mean of its divisors is an integer number (21620625991).

Almost surely, 2^43241251981 is an apocalyptic number.

It is an amenable number.

43241251981 is a deficient number, since it is larger than the sum of its proper divisors (1).

43241251981 is an equidigital number, since it uses as much as digits as its factorization.

43241251981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 40.

The spelling of 43241251981 in words is "forty-three billion, two hundred forty-one million, two hundred fifty-one thousand, nine hundred eighty-one".