55205121 has 16 divisors (see below), whose sum is σ = 75257600. Its totient is φ = 35987328.

The previous prime is 55205099. The next prime is 55205123. The reversal of 55205121 is 12150255.

It is not a de Polignac number, because 55205121 - 2⁶ = 55205057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55205123) 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 in 15 ways as a sum of consecutive naturals, for example, 24765 + ... + 26901.

It is an arithmetic number, because the mean of its divisors is an integer number (4703600).

Almost surely, 2^55205121 is an apocalyptic number.

It is an amenable number.

55205121 is a deficient number, since it is larger than the sum of its proper divisors (20052479).

55205121 is a wasteful number, since it uses less digits than its factorization.

55205121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2328.

The product of its (nonzero) digits is 500, while the sum is 21.

The square root of 55205121 is about 7430.0148721251. The cubic root of 55205121 is about 380.7674264833.

Adding to 55205121 its reverse (12150255), we get a palindrome (67355376).

The spelling of 55205121 in words is "fifty-five million, two hundred five thousand, one hundred twenty-one".