55044551221 has 4 divisors (see below), whose sum is σ = 60048601344. Its totient is φ = 50040501100.

The previous prime is 55044551203. The next prime is 55044551227. The reversal of 55044551221 is 12215544055.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55044551221 - 2¹⁷ = 55044420149 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 (55044551227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2502025045 + ... + 2502025066.

It is an arithmetic number, because the mean of its divisors is an integer number (15012150336).

Almost surely, 2^55044551221 is an apocalyptic number.

It is an amenable number.

55044551221 is a deficient number, since it is larger than the sum of its proper divisors (5004050123).

55044551221 is a wasteful number, since it uses less digits than its factorization.

55044551221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5004050122.

The product of its (nonzero) digits is 40000, while the sum is 34.

The spelling of 55044551221 in words is "fifty-five billion, forty-four million, five hundred fifty-one thousand, two hundred twenty-one".