91321547 has 2 divisors, whose sum is σ = 91321548. Its totient is φ = 91321546.

The previous prime is 91321519. The next prime is 91321583. The reversal of 91321547 is 74512319.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91321547 - 2¹⁴ = 91305163 is a prime.

It is not a weakly prime, because it can be changed into another prime (91321507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45660773 + 45660774.

It is an arithmetic number, because the mean of its divisors is an integer number (45660774).

Almost surely, 2^91321547 is an apocalyptic number.

91321547 is a deficient number, since it is larger than the sum of its proper divisors (1).

91321547 is an equidigital number, since it uses as much as digits as its factorization.

91321547 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7560, while the sum is 32.

The square root of 91321547 is about 9556.2307946177. The cubic root of 91321547 is about 450.3233018250.

The spelling of 91321547 in words is "ninety-one million, three hundred twenty-one thousand, five hundred forty-seven".