6978621 has 8 divisors (see below), whose sum is σ = 10020640. Its totient is φ = 4294512.

The previous prime is 6978617. The next prime is 6978641. The reversal of 6978621 is 1268796.

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

It is not a de Polignac number, because 6978621 - 2² = 6978617 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 178939 = 6978621 / (6 + 9 + 7 + 8 + 6 + 2 + 1).

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 6978621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6978641) 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, 89431 + ... + 89508.

It is an arithmetic number, because the mean of its divisors is an integer number (1252580).

Almost surely, 2^6978621 is an apocalyptic number.

It is an amenable number.

6978621 is a deficient number, since it is larger than the sum of its proper divisors (3042019).

6978621 is a wasteful number, since it uses less digits than its factorization.

6978621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178955.

The product of its digits is 36288, while the sum is 39.

The square root of 6978621 is about 2641.7079702344. The cubic root of 6978621 is about 191.0981741764.

The spelling of 6978621 in words is "six million, nine hundred seventy-eight thousand, six hundred twenty-one".