2199891409 has 27 divisors (see below), whose sum is σ = 2442161361. Its totient is φ = 1981182720.

The previous prime is 2199891389. The next prime is 2199891457. The reversal of 2199891409 is 9041989912.

The square root of 2199891409 is 46903.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 2907025 + 2196984384 = 1705^2 + 46872^2 .

It is not a de Polignac number, because 2199891409 - 2⁵ = 2199891377 is a prime.

It is a super-2 number, since 2×2199891409² = 9679044422784010562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2199891479) 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 26 ways as a sum of consecutive naturals, for example, 24717837 + ... + 24717925.

Almost surely, 2^2199891409 is an apocalyptic number.

2199891409 is the 46903-rd square number.

2199891409 is the 23452-nd centered octagonal number.

It is an amenable number.

2199891409 is a deficient number, since it is larger than the sum of its proper divisors (242269952).

2199891409 is an frugal number, since it uses more digits than its factorization.

2199891409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 137 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 52.

The cubic root of 2199891409 is about 1300.5700476318.

Multiplying 2199891409 by its product of nonzero digits (419904), we get a square (923743202204736 = 30393144²).

The spelling of 2199891409 in words is "two billion, one hundred ninety-nine million, eight hundred ninety-one thousand, four hundred nine".