70217221 has 2 divisors, whose sum is σ = 70217222. Its totient is φ = 70217220.

The previous prime is 70217197. The next prime is 70217239. The reversal of 70217221 is 12271207.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58752225 + 11464996 = 7665^2 + 3386^2 .

It is a cyclic number.

It is not a de Polignac number, because 70217221 - 2⁷ = 70217093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 70217192 and 70217201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70257221) 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, 35108610 + 35108611.

It is an arithmetic number, because the mean of its divisors is an integer number (35108611).

Almost surely, 2^70217221 is an apocalyptic number.

It is an amenable number.

70217221 is a deficient number, since it is larger than the sum of its proper divisors (1).

70217221 is an equidigital number, since it uses as much as digits as its factorization.

70217221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 392, while the sum is 22.

The square root of 70217221 is about 8379.5716477634. The cubic root of 70217221 is about 412.5543896449.

Adding to 70217221 its reverse (12271207), we get a palindrome (82488428).

The spelling of 70217221 in words is "seventy million, two hundred seventeen thousand, two hundred twenty-one".