919181919091 has 4 divisors (see below), whose sum is σ = 919238720472. Its totient is φ = 919125117712.

The previous prime is 919181919043. The next prime is 919181919113. The reversal of 919181919091 is 190919181919.

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

It is a cyclic number.

It is not a de Polignac number, because 919181919091 - 2³⁹ = 369426105203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (919181919011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28376410 + ... + 28408783.

It is an arithmetic number, because the mean of its divisors is an integer number (229809680118).

Almost surely, 2^919181919091 is an apocalyptic number.

919181919091 is a deficient number, since it is larger than the sum of its proper divisors (56801381).

919181919091 is a wasteful number, since it uses less digits than its factorization.

919181919091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56801380.

The product of its (nonzero) digits is 472392, while the sum is 58.

The spelling of 919181919091 in words is "nine hundred nineteen billion, one hundred eighty-one million, nine hundred nineteen thousand, ninety-one".