656340066181 has 2 divisors, whose sum is σ = 656340066182. Its totient is φ = 656340066180.

The previous prime is 656340066157. The next prime is 656340066223. The reversal of 656340066181 is 181660043656.

656340066181 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., 349600212900 + 306739853281 = 591270^2 + 553841^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656340066181 is a prime.

It is a super-2 number, since 2×656340066181² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656340066121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328170033090 + 328170033091.

It is an arithmetic number, because the mean of its divisors is an integer number (328170033091).

Almost surely, 2^656340066181 is an apocalyptic number.

It is an amenable number.

656340066181 is a deficient number, since it is larger than the sum of its proper divisors (1).

656340066181 is an equidigital number, since it uses as much as digits as its factorization.

656340066181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 46.

The spelling of 656340066181 in words is "six hundred fifty-six billion, three hundred forty million, sixty-six thousand, one hundred eighty-one".