91049839 has 2 divisors, whose sum is σ = 91049840. Its totient is φ = 91049838.

The previous prime is 91049747. The next prime is 91049867. The reversal of 91049839 is 93894019.

It is a strong prime.

It is an emirp because it is prime and its reverse (93894019) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91049839 - 2⁹ = 91049327 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91049795 and 91049804.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91049869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45524919 + 45524920.

It is an arithmetic number, because the mean of its divisors is an integer number (45524920).

Almost surely, 2^91049839 is an apocalyptic number.

91049839 is a deficient number, since it is larger than the sum of its proper divisors (1).

91049839 is an equidigital number, since it uses as much as digits as its factorization.

91049839 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 91049839 is about 9542.0039299929. The cubic root of 91049839 is about 449.8762441580.

The spelling of 91049839 in words is "ninety-one million, forty-nine thousand, eight hundred thirty-nine".