215700556217 has 2 divisors, whose sum is σ = 215700556218. Its totient is φ = 215700556216.

The previous prime is 215700556163. The next prime is 215700556237. The reversal of 215700556217 is 712655007512.

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., 185949825961 + 29750730256 = 431219^2 + 172484^2 .

It is a cyclic number.

It is not a de Polignac number, because 215700556217 - 2¹⁰ = 215700555193 is a prime.

It is not a weakly prime, because it can be changed into another prime (215700556237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107850278108 + 107850278109.

It is an arithmetic number, because the mean of its divisors is an integer number (107850278109).

Almost surely, 2^215700556217 is an apocalyptic number.

It is an amenable number.

215700556217 is a deficient number, since it is larger than the sum of its proper divisors (1).

215700556217 is an equidigital number, since it uses as much as digits as its factorization.

215700556217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 147000, while the sum is 41.

The spelling of 215700556217 in words is "two hundred fifteen billion, seven hundred million, five hundred fifty-six thousand, two hundred seventeen".