91662397 has 2 divisors, whose sum is σ = 91662398. Its totient is φ = 91662396.

The previous prime is 91662379. The next prime is 91662401. The reversal of 91662397 is 79326619.

Together with previous prime (91662379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78659161 + 13003236 = 8869^2 + 3606^2 .

It is an emirp because it is prime and its reverse (79326619) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91662397 - 2⁷ = 91662269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91662497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45831198 + 45831199.

It is an arithmetic number, because the mean of its divisors is an integer number (45831199).

Almost surely, 2^91662397 is an apocalyptic number.

It is an amenable number.

91662397 is a deficient number, since it is larger than the sum of its proper divisors (1).

91662397 is an equidigital number, since it uses as much as digits as its factorization.

91662397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122472, while the sum is 43.

The square root of 91662397 is about 9574.0480988974. The cubic root of 91662397 is about 450.8828708470.

The spelling of 91662397 in words is "ninety-one million, six hundred sixty-two thousand, three hundred ninety-seven".