2198809 has 4 divisors (see below), whose sum is σ = 2274660. Its totient is φ = 2122960.

The previous prime is 2198783. The next prime is 2198827. The reversal of 2198809 is 9088912.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1814409 + 384400 = 1347^2 + 620^2 .

It is a cyclic number.

It is not a de Polignac number, because 2198809 - 2¹⁵ = 2166041 is a prime.

It is a super-2 number, since 2×2198809² = 9669522036962, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2198879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37882 + ... + 37939.

It is an arithmetic number, because the mean of its divisors is an integer number (568665).

2^2198809 is an apocalyptic number.

2198809 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

2198809 is a deficient number, since it is larger than the sum of its proper divisors (75851).

2198809 is an equidigital number, since it uses as much as digits as its factorization.

2198809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75850.

The product of its (nonzero) digits is 10368, while the sum is 37.

The square root of 2198809 is about 1482.8381570488. The cubic root of 2198809 is about 130.0356706848.

The spelling of 2198809 in words is "two million, one hundred ninety-eight thousand, eight hundred nine".