216255257 has 2 divisors, whose sum is σ = 216255258. Its totient is φ = 216255256.

The previous prime is 216255251. The next prime is 216255271. The reversal of 216255257 is 752552612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138744841 + 77510416 = 11779^2 + 8804^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216255257 is a prime.

It is not a weakly prime, because it can be changed into another prime (216255251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108127628 + 108127629.

It is an arithmetic number, because the mean of its divisors is an integer number (108127629).

Almost surely, 2^216255257 is an apocalyptic number.

It is an amenable number.

216255257 is a deficient number, since it is larger than the sum of its proper divisors (1).

216255257 is an equidigital number, since it uses as much as digits as its factorization.

216255257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42000, while the sum is 35.

The square root of 216255257 is about 14705.6199121288. The cubic root of 216255257 is about 600.2362560337.

The spelling of 216255257 in words is "two hundred sixteen million, two hundred fifty-five thousand, two hundred fifty-seven".