655804217 has 2 divisors, whose sum is σ = 655804218. Its totient is φ = 655804216.

The previous prime is 655804183. The next prime is 655804249. The reversal of 655804217 is 712408556.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 487349776 + 168454441 = 22076^2 + 12979^2 .

It is a cyclic number.

It is not a de Polignac number, because 655804217 - 2⁶ = 655804153 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (654804217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327902108 + 327902109.

It is an arithmetic number, because the mean of its divisors is an integer number (327902109).

Almost surely, 2^655804217 is an apocalyptic number.

It is an amenable number.

655804217 is a deficient number, since it is larger than the sum of its proper divisors (1).

655804217 is an equidigital number, since it uses as much as digits as its factorization.

655804217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 67200, while the sum is 38.

The square root of 655804217 is about 25608.6746435656. The cubic root of 655804217 is about 868.8098479412.

The spelling of 655804217 in words is "six hundred fifty-five million, eight hundred four thousand, two hundred seventeen".