91445573 has 2 divisors, whose sum is σ = 91445574. Its totient is φ = 91445572.

The previous prime is 91445569. The next prime is 91445579. The reversal of 91445573 is 37554419.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89434849 + 2010724 = 9457^2 + 1418^2 .

It is a cyclic number.

It is not a de Polignac number, because 91445573 - 2² = 91445569 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91445579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45722786 + 45722787.

It is an arithmetic number, because the mean of its divisors is an integer number (45722787).

Almost surely, 2^91445573 is an apocalyptic number.

It is an amenable number.

91445573 is a deficient number, since it is larger than the sum of its proper divisors (1).

91445573 is an equidigital number, since it uses as much as digits as its factorization.

91445573 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75600, while the sum is 38.

The square root of 91445573 is about 9562.7178667992. The cubic root of 91445573 is about 450.5270745898.

The spelling of 91445573 in words is "ninety-one million, four hundred forty-five thousand, five hundred seventy-three".