491493091 has 4 divisors (see below), whose sum is σ = 491537800. Its totient is φ = 491448384.

The previous prime is 491492993. The next prime is 491493097. The reversal of 491493091 is 190394194.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 491493091 - 2¹³ = 491484899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491493097) 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, 6880 + ... + 32098.

It is an arithmetic number, because the mean of its divisors is an integer number (122884450).

Almost surely, 2^491493091 is an apocalyptic number.

491493091 is a deficient number, since it is larger than the sum of its proper divisors (44709).

491493091 is a wasteful number, since it uses less digits than its factorization.

491493091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44708.

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 491493091 is about 22169.6434567631. The cubic root of 491493091 is about 789.1734617650.

The spelling of 491493091 in words is "four hundred ninety-one million, four hundred ninety-three thousand, ninety-one".