1091796989 has 4 divisors (see below), whose sum is σ = 1092192924. Its totient is φ = 1091401056.

The previous prime is 1091796973. The next prime is 1091796991. The reversal of 1091796989 is 9896971901.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 483780025 + 608016964 = 21995^2 + 24658^2 .

It is a cyclic number.

It is not a de Polignac number, because 1091796989 - 2⁴ = 1091796973 is a prime.

It is a super-3 number, since 3×1091796989³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091796919) 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 in 3 ways as a sum of consecutive naturals, for example, 193802 + ... + 199355.

It is an arithmetic number, because the mean of its divisors is an integer number (273048231).

Almost surely, 2^1091796989 is an apocalyptic number.

It is an amenable number.

1091796989 is a deficient number, since it is larger than the sum of its proper divisors (395935).

1091796989 is an equidigital number, since it uses as much as digits as its factorization.

1091796989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395934.

The product of its (nonzero) digits is 2204496, while the sum is 59.

The square root of 1091796989 is about 33042.3514447746. The cubic root of 1091796989 is about 1029.7077088741.

The spelling of 1091796989 in words is "one billion, ninety-one million, seven hundred ninety-six thousand, nine hundred eighty-nine".