91285897 has 2 divisors, whose sum is σ = 91285898. Its totient is φ = 91285896.

The previous prime is 91285879. The next prime is 91285933. The reversal of 91285897 is 79858219.

Together with previous prime (91285879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81432576 + 9853321 = 9024^2 + 3139^2 .

It is a cyclic number.

It is not a de Polignac number, because 91285897 - 2¹⁹ = 90761609 is a prime.

It is a super-2 number, since 2×91285897² = 16666229982189218, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91285897.

It is not a weakly prime, because it can be changed into another prime (91285867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45642948 + 45642949.

It is an arithmetic number, because the mean of its divisors is an integer number (45642949).

Almost surely, 2^91285897 is an apocalyptic number.

It is an amenable number.

91285897 is a deficient number, since it is larger than the sum of its proper divisors (1).

91285897 is an equidigital number, since it uses as much as digits as its factorization.

91285897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 362880, while the sum is 49.

The square root of 91285897 is about 9554.3653373733. The cubic root of 91285897 is about 450.2646953014.

The spelling of 91285897 in words is "ninety-one million, two hundred eighty-five thousand, eight hundred ninety-seven".