2811944221 has 4 divisors (see below), whose sum is σ = 2812075200. Its totient is φ = 2811813244.

The previous prime is 2811944183. The next prime is 2811944237. The reversal of 2811944221 is 1224491182.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2811944221 - 2⁹ = 2811943709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2811914221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24901 + ... + 79018.

It is an arithmetic number, because the mean of its divisors is an integer number (703018800).

Almost surely, 2^2811944221 is an apocalyptic number.

It is an amenable number.

2811944221 is a deficient number, since it is larger than the sum of its proper divisors (130979).

2811944221 is a wasteful number, since it uses less digits than its factorization.

2811944221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130978.

The product of its digits is 9216, while the sum is 34.

The square root of 2811944221 is about 53027.7683954360. The cubic root of 2811944221 is about 1411.4610579851.

The spelling of 2811944221 in words is "two billion, eight hundred eleven million, nine hundred forty-four thousand, two hundred twenty-one".