1091959091 has 4 divisors (see below), whose sum is σ = 1092089784. Its totient is φ = 1091828400.

The previous prime is 1091959073. The next prime is 1091959111. The reversal of 1091959091 is 1909591901.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1909591901 = 7 ⋅272798843.

It is a cyclic number.

It is not a de Polignac number, because 1091959091 - 2¹⁰ = 1091958067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1091959061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51890 + ... + 69831.

It is an arithmetic number, because the mean of its divisors is an integer number (273022446).

Almost surely, 2^1091959091 is an apocalyptic number.

1091959091 is a deficient number, since it is larger than the sum of its proper divisors (130693).

1091959091 is an equidigital number, since it uses as much as digits as its factorization.

1091959091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130692.

The product of its (nonzero) digits is 32805, while the sum is 44.

The square root of 1091959091 is about 33044.8042965910. The cubic root of 1091959091 is about 1029.7586674987.

The spelling of 1091959091 in words is "one billion, ninety-one million, nine hundred fifty-nine thousand, ninety-one".