7872217 has 2 divisors, whose sum is σ = 7872218. Its totient is φ = 7872216.

The previous prime is 7872191. The next prime is 7872223. The reversal of 7872217 is 7122787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7862416 + 9801 = 2804^2 + 99^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7872217 is a prime.

It is an Ulam number.

7872217 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (7872017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3936108 + 3936109.

It is an arithmetic number, because the mean of its divisors is an integer number (3936109).

Almost surely, 2^7872217 is an apocalyptic number.

It is an amenable number.

7872217 is a deficient number, since it is larger than the sum of its proper divisors (1).

7872217 is an equidigital number, since it uses as much as digits as its factorization.

It is an anagram of its base 12 representation: 7872217 = (2777821)₁₂.

7872217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10976, while the sum is 34.

The square root of 7872217 is about 2805.7471375732. The cubic root of 7872217 is about 198.9294211971.

The spelling of 7872217 in words is "seven million, eight hundred seventy-two thousand, two hundred seventeen".