55705841981 has 2 divisors, whose sum is σ = 55705841982. Its totient is φ = 55705841980.

The previous prime is 55705841977. The next prime is 55705842001. The reversal of 55705841981 is 18914850755.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55158749881 + 547092100 = 234859^2 + 23390^2 .

It is a cyclic number.

It is not a de Polignac number, because 55705841981 - 2² = 55705841977 is a prime.

It is a super-2 number, since 2×55705841981² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55705841941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27852920990 + 27852920991.

It is an arithmetic number, because the mean of its divisors is an integer number (27852920991).

Almost surely, 2^55705841981 is an apocalyptic number.

It is an amenable number.

55705841981 is a deficient number, since it is larger than the sum of its proper divisors (1).

55705841981 is an equidigital number, since it uses as much as digits as its factorization.

55705841981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016000, while the sum is 53.

The spelling of 55705841981 in words is "fifty-five billion, seven hundred five million, eight hundred forty-one thousand, nine hundred eighty-one".