55513321 has 2 divisors, whose sum is σ = 55513322. Its totient is φ = 55513320.

The previous prime is 55513309. The next prime is 55513331. The reversal of 55513321 is 12331555.

55513321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51265600 + 4247721 = 7160^2 + 2061^2 .

It is a cyclic number.

It is not a de Polignac number, because 55513321 - 2¹³ = 55505129 is a prime.

It is not a weakly prime, because it can be changed into another prime (55513331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27756660 + 27756661.

It is an arithmetic number, because the mean of its divisors is an integer number (27756661).

Almost surely, 2^55513321 is an apocalyptic number.

It is an amenable number.

55513321 is a deficient number, since it is larger than the sum of its proper divisors (1).

55513321 is an equidigital number, since it uses as much as digits as its factorization.

55513321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2250, while the sum is 25.

The square root of 55513321 is about 7450.7262062164. The cubic root of 55513321 is about 381.4746966768.

Adding to 55513321 its reverse (12331555), we get a palindrome (67844876).

The spelling of 55513321 in words is "fifty-five million, five hundred thirteen thousand, three hundred twenty-one".