91444081 has 2 divisors, whose sum is σ = 91444082. Its totient is φ = 91444080.

The previous prime is 91444061. The next prime is 91444099. The reversal of 91444081 is 18044419.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84474481 + 6969600 = 9191^2 + 2640^2 .

It is a cyclic number.

It is not a de Polignac number, because 91444081 - 2¹⁷ = 91313009 is a prime.

It is a super-2 number, since 2×91444081² = 16724039899869122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91444061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45722040 + 45722041.

It is an arithmetic number, because the mean of its divisors is an integer number (45722041).

Almost surely, 2^91444081 is an apocalyptic number.

It is an amenable number.

91444081 is a deficient number, since it is larger than the sum of its proper divisors (1).

91444081 is an equidigital number, since it uses as much as digits as its factorization.

91444081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 91444081 is about 9562.6398551864. The cubic root of 91444081 is about 450.5246243525.

It can be divided in two parts, 9144 and 4081, that added together give a square (13225 = 115²).

The spelling of 91444081 in words is "ninety-one million, four hundred forty-four thousand, eighty-one".