55543221 has 6 divisors (see below), whose sum is σ = 80229110. Its totient is φ = 37028808.

The previous prime is 55543219. The next prime is 55543231. The reversal of 55543221 is 12234555.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 47196900 + 8346321 = 6870^2 + 2889^2 .

It is not a de Polignac number, because 55543221 - 2¹ = 55543219 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55543211) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3085726 + ... + 3085743.

Almost surely, 2^55543221 is an apocalyptic number.

It is an amenable number.

55543221 is a deficient number, since it is larger than the sum of its proper divisors (24685889).

55543221 is a wasteful number, since it uses less digits than its factorization.

55543221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6171475 (or 6171472 counting only the distinct ones).

The product of its digits is 6000, while the sum is 27.

The square root of 55543221 is about 7452.7324519266. The cubic root of 55543221 is about 381.5431730114.

Adding to 55543221 its reverse (12234555), we get a palindrome (67777776).

The spelling of 55543221 in words is "fifty-five million, five hundred forty-three thousand, two hundred twenty-one".