6978391 has 8 divisors (see below), whose sum is σ = 8072064. Its totient is φ = 5908920.

The previous prime is 6978383. The next prime is 6978421. The reversal of 6978391 is 1938796.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6978391 - 2³ = 6978383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6978371) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5425 + ... + 6586.

It is an arithmetic number, because the mean of its divisors is an integer number (1009008).

Almost surely, 2^6978391 is an apocalyptic number.

6978391 is a deficient number, since it is larger than the sum of its proper divisors (1093673).

6978391 is a wasteful number, since it uses less digits than its factorization.

6978391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12101.

The product of its digits is 81648, while the sum is 43.

The square root of 6978391 is about 2641.6644374333. The cubic root of 6978391 is about 191.0960747614.

The spelling of 6978391 in words is "six million, nine hundred seventy-eight thousand, three hundred ninety-one".