2191718905 has 8 divisors (see below), whose sum is σ = 2631733632. Its totient is φ = 1752261168.

The previous prime is 2191718849. The next prime is 2191718909. The reversal of 2191718905 is 5098171912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2191718905 - 2¹³ = 2191710713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2191718909) 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 7 ways as a sum of consecutive naturals, for example, 130539 + ... + 146368.

It is an arithmetic number, because the mean of its divisors is an integer number (328966704).

Almost surely, 2^2191718905 is an apocalyptic number.

It is an amenable number.

2191718905 is a deficient number, since it is larger than the sum of its proper divisors (440014727).

2191718905 is a wasteful number, since it uses less digits than its factorization.

2191718905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278495.

The product of its (nonzero) digits is 45360, while the sum is 43.

The square root of 2191718905 is about 46815.7976008099. The cubic root of 2191718905 is about 1298.9575281691.

The spelling of 2191718905 in words is "two billion, one hundred ninety-one million, seven hundred eighteen thousand, nine hundred five".