2191220000 has 90 divisors (see below), whose sum is σ = 5407065279. Its totient is φ = 873840000.

The previous prime is 2191219991. The next prime is 2191220021. The reversal of 2191220000 is 221912.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 3 ways, for example, as 506610064 + 1684609936 = 22508^2 + 41044^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=33100.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 6619835 + ... + 6620165.

Almost surely, 2^2191220000 is an apocalyptic number.

2191220000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2191220000

2191220000 is an abundant number, since it is smaller than the sum of its proper divisors (3215845279).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2191220000 is an frugal number, since it uses more digits than its factorization.

2191220000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 2191220000 is about 46810.4689145494. The cubic root of 2191220000 is about 1298.8589593270.

Multiplying 2191220000 by its product of nonzero digits (72), we get a square (157767840000 = 397200²).

Adding to 2191220000 its reverse (221912), we get a palindrome (2191441912).

The spelling of 2191220000 in words is "two billion, one hundred ninety-one million, two hundred twenty thousand".