91031011 has 2 divisors, whose sum is σ = 91031012. Its totient is φ = 91031010.

The previous prime is 91031009. The next prime is 91031021. The reversal of 91031011 is 11013019.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91031011 - 2¹ = 91031009 is a prime.

Together with 91031009, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (91031021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45515505 + 45515506.

It is an arithmetic number, because the mean of its divisors is an integer number (45515506).

Almost surely, 2^91031011 is an apocalyptic number.

91031011 is a deficient number, since it is larger than the sum of its proper divisors (1).

91031011 is an equidigital number, since it uses as much as digits as its factorization.

91031011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27, while the sum is 16.

The square root of 91031011 is about 9541.0172937690. The cubic root of 91031011 is about 449.8452323739.

The spelling of 91031011 in words is "ninety-one million, thirty-one thousand, eleven".