213856717 has 2 divisors, whose sum is σ = 213856718. Its totient is φ = 213856716.

The previous prime is 213856711. The next prime is 213856739. The reversal of 213856717 is 717658312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 210656196 + 3200521 = 14514^2 + 1789^2 .

It is a cyclic number.

It is not a de Polignac number, because 213856717 - 2²⁷ = 79638989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 213856717.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213856711) 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, 106928358 + 106928359.

It is an arithmetic number, because the mean of its divisors is an integer number (106928359).

Almost surely, 2^213856717 is an apocalyptic number.

It is an amenable number.

213856717 is a deficient number, since it is larger than the sum of its proper divisors (1).

213856717 is an equidigital number, since it uses as much as digits as its factorization.

213856717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 70560, while the sum is 40.

The square root of 213856717 is about 14623.8407061893. The cubic root of 213856717 is about 598.0088784042.

The spelling of 213856717 in words is "two hundred thirteen million, eight hundred fifty-six thousand, seven hundred seventeen".