2978209 has 4 divisors (see below), whose sum is σ = 3207316. Its totient is φ = 2749104.

The previous prime is 2978197. The next prime is 2978219. The reversal of 2978209 is 9028792.

2978209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 861184 + 2117025 = 928^2 + 1455^2 .

It is a cyclic number.

It is not a de Polignac number, because 2978209 - 2⁵ = 2978177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2978219) 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, 114534 + ... + 114559.

It is an arithmetic number, because the mean of its divisors is an integer number (801829).

2^2978209 is an apocalyptic number.

It is an amenable number.

2978209 is a deficient number, since it is larger than the sum of its proper divisors (229107).

2978209 is a wasteful number, since it uses less digits than its factorization.

2978209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229106.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 2978209 is about 1725.7488229751. The cubic root of 2978209 is about 143.8749074389.

The spelling of 2978209 in words is "two million, nine hundred seventy-eight thousand, two hundred nine".