2199200021 has 4 divisors (see below), whose sum is σ = 2199498444. Its totient is φ = 2198901600.

The previous prime is 2199200009. The next prime is 2199200033. The reversal of 2199200021 is 1200029912.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2199200009) and next prime (2199200033).

It can be written as a sum of positive squares in 2 ways, for example, as 219928900 + 1979271121 = 14830^2 + 44489^2 .

It is a cyclic number.

It is not a de Polignac number, because 2199200021 - 2¹⁰ = 2199198997 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 (2199200051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137870 + ... + 152991.

It is an arithmetic number, because the mean of its divisors is an integer number (549874611).

Almost surely, 2^2199200021 is an apocalyptic number.

It is an amenable number.

2199200021 is a deficient number, since it is larger than the sum of its proper divisors (298423).

2199200021 is an equidigital number, since it uses as much as digits as its factorization.

2199200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298422.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 2199200021 is about 46895.6290180652. The cubic root of 2199200021 is about 1300.4337844299.

Adding to 2199200021 its reverse (1200029912), we get a palindrome (3399229933).

The spelling of 2199200021 in words is "two billion, one hundred ninety-nine million, two hundred thousand, twenty-one".