43191055021 has 2 divisors, whose sum is σ = 43191055022. Its totient is φ = 43191055020.

The previous prime is 43191054989. The next prime is 43191055069. The reversal of 43191055021 is 12055019134.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42296446921 + 894608100 = 205661^2 + 29910^2 .

It is a cyclic number.

It is not a de Polignac number, because 43191055021 - 2⁵ = 43191054989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43191055091) 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, 21595527510 + 21595527511.

It is an arithmetic number, because the mean of its divisors is an integer number (21595527511).

Almost surely, 2^43191055021 is an apocalyptic number.

It is an amenable number.

43191055021 is a deficient number, since it is larger than the sum of its proper divisors (1).

43191055021 is an equidigital number, since it uses as much as digits as its factorization.

43191055021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 31.

The spelling of 43191055021 in words is "forty-three billion, one hundred ninety-one million, fifty-five thousand, twenty-one".