91134221 has 2 divisors, whose sum is σ = 91134222. Its totient is φ = 91134220.

The previous prime is 91134191. The next prime is 91134223. The reversal of 91134221 is 12243119.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74200996 + 16933225 = 8614^2 + 4115^2 .

It is a cyclic number.

It is not a de Polignac number, because 91134221 - 2¹⁰ = 91133197 is a prime.

Together with 91134223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91134223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45567110 + 45567111.

It is an arithmetic number, because the mean of its divisors is an integer number (45567111).

Almost surely, 2^91134221 is an apocalyptic number.

It is an amenable number.

91134221 is a deficient number, since it is larger than the sum of its proper divisors (1).

91134221 is an equidigital number, since it uses as much as digits as its factorization.

91134221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432, while the sum is 23.

The square root of 91134221 is about 9546.4245139214. The cubic root of 91134221 is about 450.0151780889.

The spelling of 91134221 in words is "ninety-one million, one hundred thirty-four thousand, two hundred twenty-one".