919091 has 4 divisors (see below), whose sum is σ = 921072. Its totient is φ = 917112.

The previous prime is 919081. The next prime is 919109. The reversal of 919091 is 190919.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190919 = 71 ⋅2689.

It is a cyclic number.

It is not a de Polignac number, because 919091 - 2¹⁰ = 918067 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (919021) 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, 125 + ... + 1361.

It is an arithmetic number, because the mean of its divisors is an integer number (230268).

2⁹¹⁹⁰⁹¹ is an apocalyptic number.

919091 is a deficient number, since it is larger than the sum of its proper divisors (1981).

919091 is a wasteful number, since it uses less digits than its factorization.

919091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1980.

The product of its (nonzero) digits is 729, while the sum is 29.

The square root of 919091 is about 958.6923385529. The cubic root of 919091 is about 97.2268400649.

The spelling of 919091 in words is "nine hundred nineteen thousand, ninety-one".