7978217 has 8 divisors (see below), whose sum is σ = 8965824. Its totient is φ = 7044048.

The previous prime is 7978211. The next prime is 7978237. The reversal of 7978217 is 7128797.

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 7978217 - 2⁸ = 7977961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7978211) 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, 13043 + ... + 13640.

It is an arithmetic number, because the mean of its divisors is an integer number (1120728).

Almost surely, 2^7978217 is an apocalyptic number.

It is an amenable number.

7978217 is a deficient number, since it is larger than the sum of its proper divisors (987607).

7978217 is a wasteful number, since it uses less digits than its factorization.

7978217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26719.

The product of its digits is 49392, while the sum is 41.

The square root of 7978217 is about 2824.5737731559. The cubic root of 7978217 is about 199.8183099937.

The spelling of 7978217 in words is "seven million, nine hundred seventy-eight thousand, two hundred seventeen".