91476809 has 2 divisors, whose sum is σ = 91476810. Its totient is φ = 91476808.

The previous prime is 91476797. The next prime is 91476823. The reversal of 91476809 is 90867419.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60918025 + 30558784 = 7805^2 + 5528^2 .

It is a cyclic number.

It is not a de Polignac number, because 91476809 - 2⁴ = 91476793 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 91476809.

It is not a weakly prime, because it can be changed into another prime (91476829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45738404 + 45738405.

It is an arithmetic number, because the mean of its divisors is an integer number (45738405).

Almost surely, 2^91476809 is an apocalyptic number.

It is an amenable number.

91476809 is a deficient number, since it is larger than the sum of its proper divisors (1).

91476809 is an equidigital number, since it uses as much as digits as its factorization.

91476809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 91476809 is about 9564.3509450459. The cubic root of 91476809 is about 450.5783657977.

The spelling of 91476809 in words is "ninety-one million, four hundred seventy-six thousand, eight hundred nine".