55121201 has 2 divisors, whose sum is σ = 55121202. Its totient is φ = 55121200.

The previous prime is 55121159. The next prime is 55121207. The reversal of 55121201 is 10212155.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54760000 + 361201 = 7400^2 + 601^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55121201 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55121201.

It is not a weakly prime, because it can be changed into another prime (55121207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27560600 + 27560601.

It is an arithmetic number, because the mean of its divisors is an integer number (27560601).

Almost surely, 2^55121201 is an apocalyptic number.

It is an amenable number.

55121201 is a deficient number, since it is larger than the sum of its proper divisors (1).

55121201 is an equidigital number, since it uses as much as digits as its factorization.

55121201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 55121201 is about 7424.3653600830. The cubic root of 55121201 is about 380.5743875818.

Adding to 55121201 its reverse (10212155), we get a palindrome (65333356).

The spelling of 55121201 in words is "fifty-five million, one hundred twenty-one thousand, two hundred one".