55842221 has 4 divisors (see below), whose sum is σ = 56418012. Its totient is φ = 55266432.

The previous prime is 55842209. The next prime is 55842223. The reversal of 55842221 is 12224855.

55842221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12348196 + 43494025 = 3514^2 + 6595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55842221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55842223) 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 in 3 ways as a sum of consecutive naturals, for example, 287750 + ... + 287943.

It is an arithmetic number, because the mean of its divisors is an integer number (14104503).

Almost surely, 2^55842221 is an apocalyptic number.

It is an amenable number.

55842221 is a deficient number, since it is larger than the sum of its proper divisors (575791).

55842221 is an equidigital number, since it uses as much as digits as its factorization.

55842221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 575790.

The product of its digits is 6400, while the sum is 29.

The square root of 55842221 is about 7472.7652846854. The cubic root of 55842221 is about 382.2265886123.

The spelling of 55842221 in words is "fifty-five million, eight hundred forty-two thousand, two hundred twenty-one".