661117271 has 2 divisors, whose sum is σ = 661117272. Its totient is φ = 661117270.

The previous prime is 661117241. The next prime is 661117309. The reversal of 661117271 is 172711166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661117271 - 2¹⁴ = 661100887 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661117211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330558635 + 330558636.

It is an arithmetic number, because the mean of its divisors is an integer number (330558636).

Almost surely, 2^661117271 is an apocalyptic number.

661117271 is a deficient number, since it is larger than the sum of its proper divisors (1).

661117271 is an equidigital number, since it uses as much as digits as its factorization.

661117271 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3528, while the sum is 32.

The square root of 661117271 is about 25712.2008198443. The cubic root of 661117271 is about 871.1497859865.

The spelling of 661117271 in words is "six hundred sixty-one million, one hundred seventeen thousand, two hundred seventy-one".