55103156561 has 2 divisors, whose sum is σ = 55103156562. Its totient is φ = 55103156560.

The previous prime is 55103156509. The next prime is 55103156629. The reversal of 55103156561 is 16565130155.

55103156561 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., 53937275536 + 1165881025 = 232244^2 + 34145^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55103156561 is a prime.

It is not a weakly prime, because it can be changed into another prime (55103156461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27551578280 + 27551578281.

It is an arithmetic number, because the mean of its divisors is an integer number (27551578281).

Almost surely, 2^55103156561 is an apocalyptic number.

It is an amenable number.

55103156561 is a deficient number, since it is larger than the sum of its proper divisors (1).

55103156561 is an equidigital number, since it uses as much as digits as its factorization.

55103156561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 67500, while the sum is 38.

The spelling of 55103156561 in words is "fifty-five billion, one hundred three million, one hundred fifty-six thousand, five hundred sixty-one".