1811220849 has 24 divisors (see below), whose sum is σ = 2740937472. Its totient is φ = 1151076960.

The previous prime is 1811220841. The next prime is 1811220871. The reversal of 1811220849 is 9480221181.

It is a happy number.

It is not a de Polignac number, because 1811220849 - 2³ = 1811220841 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1811220841) 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 23 ways as a sum of consecutive naturals, for example, 29754 + ... + 67139.

It is an arithmetic number, because the mean of its divisors is an integer number (114205728).

Almost surely, 2^1811220849 is an apocalyptic number.

It is an amenable number.

1811220849 is a deficient number, since it is larger than the sum of its proper divisors (929716623).

1811220849 is a wasteful number, since it uses less digits than its factorization.

1811220849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96997 (or 96994 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 1811220849 is about 42558.4403967063. The cubic root of 1811220849 is about 1218.9628489471.

The spelling of 1811220849 in words is "one billion, eight hundred eleven million, two hundred twenty thousand, eight hundred forty-nine".