1991010041 has 2 divisors, whose sum is σ = 1991010042. Its totient is φ = 1991010040.

The previous prime is 1991010013. The next prime is 1991010067. The reversal of 1991010041 is 1400101991.

It is an a-pointer prime, because the next prime (1991010067) can be obtained adding 1991010041 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1916688400 + 74321641 = 43780^2 + 8621^2 .

It is a cyclic number.

It is not a de Polignac number, because 1991010041 - 2¹⁰ = 1991009017 is a prime.

It is not a weakly prime, because it can be changed into another prime (1991012041) 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, 995505020 + 995505021.

It is an arithmetic number, because the mean of its divisors is an integer number (995505021).

Almost surely, 2^1991010041 is an apocalyptic number.

It is an amenable number.

1991010041 is a deficient number, since it is larger than the sum of its proper divisors (1).

1991010041 is an equidigital number, since it uses as much as digits as its factorization.

1991010041 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 26.

The square root of 1991010041 is about 44620.7355497419. The cubic root of 1991010041 is about 1258.0304412129.

The spelling of 1991010041 in words is "one billion, nine hundred ninety-one million, ten thousand, forty-one".