55100009981 has 2 divisors, whose sum is σ = 55100009982. Its totient is φ = 55100009980.

The previous prime is 55100009971. The next prime is 55100010023. The reversal of 55100009981 is 18990000155.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48283030756 + 6816979225 = 219734^2 + 82565^2 .

It is a cyclic number.

It is not a de Polignac number, because 55100009981 - 2⁶ = 55100009917 is a prime.

It is a super-2 number, since 2×55100009981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55100009971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27550004990 + 27550004991.

It is an arithmetic number, because the mean of its divisors is an integer number (27550004991).

Almost surely, 2^55100009981 is an apocalyptic number.

It is an amenable number.

55100009981 is a deficient number, since it is larger than the sum of its proper divisors (1).

55100009981 is an equidigital number, since it uses as much as digits as its factorization.

55100009981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 38.

The spelling of 55100009981 in words is "fifty-five billion, one hundred million, nine thousand, nine hundred eighty-one".