217356961 has 2 divisors, whose sum is σ = 217356962. Its totient is φ = 217356960.

The previous prime is 217356947. The next prime is 217356977. The reversal of 217356961 is 169653712.

217356961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 208975936 + 8381025 = 14456^2 + 2895^2 .

It is a cyclic number.

It is not a de Polignac number, because 217356961 - 2⁵ = 217356929 is a prime.

It is a Chen prime.

It is equal to p_11985079 and since 217356961 and 11985079 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (217356991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108678480 + 108678481.

It is an arithmetic number, because the mean of its divisors is an integer number (108678481).

Almost surely, 2^217356961 is an apocalyptic number.

It is an amenable number.

217356961 is a deficient number, since it is larger than the sum of its proper divisors (1).

217356961 is an equidigital number, since it uses as much as digits as its factorization.

217356961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 40.

The square root of 217356961 is about 14743.0309299004. The cubic root of 217356961 is about 601.2538234233.

The spelling of 217356961 in words is "two hundred seventeen million, three hundred fifty-six thousand, nine hundred sixty-one".