91011 has 8 divisors (see below), whose sum is σ = 126720. Its totient is φ = 57992.

The previous prime is 91009. The next prime is 91019. The reversal of 91011 is 11019.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91011 - 2¹ = 91009 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 591 + ... + 728.

It is an arithmetic number, because the mean of its divisors is an integer number (15840).

2⁹¹⁰¹¹ is an apocalyptic number.

91011 is a deficient number, since it is larger than the sum of its proper divisors (35709).

91011 is a wasteful number, since it uses less digits than its factorization.

91011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1345.

The product of its (nonzero) digits is 9, while the sum is 12.

The square root of 91011 is about 301.6802943515. The cubic root of 91011 is about 44.9812267371.

The spelling of 91011 in words is "ninety-one thousand, eleven".