2978191 has 4 divisors (see below), whose sum is σ = 3008992. Its totient is φ = 2947392.

The previous prime is 2978189. The next prime is 2978197. The reversal of 2978191 is 1918792.

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

It is a cyclic number.

It is not a de Polignac number, because 2978191 - 2¹ = 2978189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2978191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2978197) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 15255 + ... + 15448.

It is an arithmetic number, because the mean of its divisors is an integer number (752248).

2^2978191 is an apocalyptic number.

2978191 is a deficient number, since it is larger than the sum of its proper divisors (30801).

2978191 is an equidigital number, since it uses as much as digits as its factorization.

2978191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30800.

The product of its digits is 9072, while the sum is 37.

The square root of 2978191 is about 1725.7436078398. The cubic root of 2978191 is about 143.8746175831.

The spelling of 2978191 in words is "two million, nine hundred seventy-eight thousand, one hundred ninety-one".