7218472817 has 2 divisors, whose sum is σ = 7218472818. Its totient is φ = 7218472816.

The previous prime is 7218472813. The next prime is 7218472819. The reversal of 7218472817 is 7182748127.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3819116401 + 3399356416 = 61799^2 + 58304^2 .

It is a cyclic number.

It is not a de Polignac number, because 7218472817 - 2² = 7218472813 is a prime.

Together with 7218472819, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7218472813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3609236408 + 3609236409.

It is an arithmetic number, because the mean of its divisors is an integer number (3609236409).

Almost surely, 2^7218472817 is an apocalyptic number.

It is an amenable number.

7218472817 is a deficient number, since it is larger than the sum of its proper divisors (1).

7218472817 is an equidigital number, since it uses as much as digits as its factorization.

7218472817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 351232, while the sum is 47.

The square root of 7218472817 is about 84961.5961302517. The cubic root of 7218472817 is about 1932.6287763645.

The spelling of 7218472817 in words is "seven billion, two hundred eighteen million, four hundred seventy-two thousand, eight hundred seventeen".