20442043991 has 2 divisors, whose sum is σ = 20442043992. Its totient is φ = 20442043990.

The previous prime is 20442043987. The next prime is 20442044017. The reversal of 20442043991 is 19934024402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20442043991 - 2² = 20442043987 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20442043291) 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, 10221021995 + 10221021996.

It is an arithmetic number, because the mean of its divisors is an integer number (10221021996).

Almost surely, 2^20442043991 is an apocalyptic number.

20442043991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20442043991 is an equidigital number, since it uses as much as digits as its factorization.

20442043991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 38.

The spelling of 20442043991 in words is "twenty billion, four hundred forty-two million, forty-three thousand, nine hundred ninety-one".