217825961 has 2 divisors, whose sum is σ = 217825962. Its totient is φ = 217825960.

The previous prime is 217825957. The next prime is 217825967. The reversal of 217825961 is 169528712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205750336 + 12075625 = 14344^2 + 3475^2 .

It is a cyclic number.

It is not a de Polignac number, because 217825961 - 2² = 217825957 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (217825967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108912980 + 108912981.

It is an arithmetic number, because the mean of its divisors is an integer number (108912981).

Almost surely, 2^217825961 is an apocalyptic number.

It is an amenable number.

217825961 is a deficient number, since it is larger than the sum of its proper divisors (1).

217825961 is an equidigital number, since it uses as much as digits as its factorization.

217825961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 41.

The square root of 217825961 is about 14758.9281792412. The cubic root of 217825961 is about 601.6859627417.

The spelling of 217825961 in words is "two hundred seventeen million, eight hundred twenty-five thousand, nine hundred sixty-one".