91009837 has 2 divisors, whose sum is σ = 91009838. Its totient is φ = 91009836.

The previous prime is 91009799. The next prime is 91009889. The reversal of 91009837 is 73890019.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75533481 + 15476356 = 8691^2 + 3934^2 .

It is a cyclic number.

It is not a de Polignac number, because 91009837 - 2¹¹ = 91007789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91009796 and 91009805.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91009637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45504918 + 45504919.

It is an arithmetic number, because the mean of its divisors is an integer number (45504919).

Almost surely, 2^91009837 is an apocalyptic number.

It is an amenable number.

91009837 is a deficient number, since it is larger than the sum of its proper divisors (1).

91009837 is an equidigital number, since it uses as much as digits as its factorization.

91009837 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 37.

The square root of 91009837 is about 9539.9075991332. The cubic root of 91009837 is about 449.8103513612.

The spelling of 91009837 in words is "ninety-one million, nine thousand, eight hundred thirty-seven".