91420591 has 2 divisors, whose sum is σ = 91420592. Its totient is φ = 91420590.

The previous prime is 91420541. The next prime is 91420597. The reversal of 91420591 is 19502419.

It is a strong prime.

It is an emirp because it is prime and its reverse (19502419) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91420591 - 2⁹ = 91420079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91420597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45710295 + 45710296.

It is an arithmetic number, because the mean of its divisors is an integer number (45710296).

Almost surely, 2^91420591 is an apocalyptic number.

91420591 is a deficient number, since it is larger than the sum of its proper divisors (1).

91420591 is an equidigital number, since it uses as much as digits as its factorization.

91420591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 91420591 is about 9561.4115589697. The cubic root of 91420591 is about 450.4860443824.

The spelling of 91420591 in words is "ninety-one million, four hundred twenty thousand, five hundred ninety-one".