6978145 has 4 divisors (see below), whose sum is σ = 8373780. Its totient is φ = 5582512.

The previous prime is 6978133. The next prime is 6978161. The reversal of 6978145 is 5418796.

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 1628176 + 5349969 = 1276^2 + 2313^2 .

It is a cyclic number.

It is not a de Polignac number, because 6978145 - 2⁵ = 6978113 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

6978145 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 6978098 and 6978107.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 697810 + ... + 697819.

It is an arithmetic number, because the mean of its divisors is an integer number (2093445).

Almost surely, 2^6978145 is an apocalyptic number.

It is an amenable number.

6978145 is a deficient number, since it is larger than the sum of its proper divisors (1395635).

6978145 is a wasteful number, since it uses less digits than its factorization.

6978145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1395634.

The product of its digits is 60480, while the sum is 40.

The square root of 6978145 is about 2641.6178754695. The cubic root of 6978145 is about 191.0938292492.

The spelling of 6978145 in words is "six million, nine hundred seventy-eight thousand, one hundred forty-five".