1091785009 has 8 divisors (see below), whose sum is σ = 1250808320. Its totient is φ = 933525216.

The previous prime is 1091784971. The next prime is 1091785027. The reversal of 1091785009 is 9005871901.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1091785009 - 2²¹ = 1089687857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1091789009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187809 + ... + 193534.

It is an arithmetic number, because the mean of its divisors is an integer number (156351040).

Almost surely, 2^1091785009 is an apocalyptic number.

It is an amenable number.

1091785009 is a deficient number, since it is larger than the sum of its proper divisors (159023311).

1091785009 is an equidigital number, since it uses as much as digits as its factorization.

1091785009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381759.

The product of its (nonzero) digits is 22680, while the sum is 40.

The square root of 1091785009 is about 33042.1701617796. The cubic root of 1091785009 is about 1029.7039426234.

The spelling of 1091785009 in words is "one billion, ninety-one million, seven hundred eighty-five thousand, nine".