91478573 has 2 divisors, whose sum is σ = 91478574. Its totient is φ = 91478572.

The previous prime is 91478549. The next prime is 91478609. The reversal of 91478573 is 37587419.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89832484 + 1646089 = 9478^2 + 1283^2 .

It is an emirp because it is prime and its reverse (37587419) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91478573 - 2¹⁰ = 91477549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91478773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45739286 + 45739287.

It is an arithmetic number, because the mean of its divisors is an integer number (45739287).

Almost surely, 2^91478573 is an apocalyptic number.

It is an amenable number.

91478573 is a deficient number, since it is larger than the sum of its proper divisors (1).

91478573 is an equidigital number, since it uses as much as digits as its factorization.

91478573 is an evil number, because the sum of its binary digits is even.

The product of its digits is 211680, while the sum is 44.

The square root of 91478573 is about 9564.4431620456. The cubic root of 91478573 is about 450.5812620331.

The spelling of 91478573 in words is "ninety-one million, four hundred seventy-eight thousand, five hundred seventy-three".