91393787 has 2 divisors, whose sum is σ = 91393788. Its totient is φ = 91393786.

The previous prime is 91393739. The next prime is 91393793. The reversal of 91393787 is 78739319.

It is a strong prime.

It is an emirp because it is prime and its reverse (78739319) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91393787 - 2⁸ = 91393531 is a prime.

It is not a weakly prime, because it can be changed into another prime (91393187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45696893 + 45696894.

It is an arithmetic number, because the mean of its divisors is an integer number (45696894).

Almost surely, 2^91393787 is an apocalyptic number.

91393787 is a deficient number, since it is larger than the sum of its proper divisors (1).

91393787 is an equidigital number, since it uses as much as digits as its factorization.

91393787 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 285768, while the sum is 47.

The square root of 91393787 is about 9560.0097803297. The cubic root of 91393787 is about 450.4420134259.

The spelling of 91393787 in words is "ninety-one million, three hundred ninety-three thousand, seven hundred eighty-seven".