855543221 has 4 divisors (see below), whose sum is σ = 921354252. Its totient is φ = 789732192.

The previous prime is 855543211. The next prime is 855543233. The reversal of 855543221 is 122345558.

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 143400625 + 712142596 = 11975^2 + 26686^2 .

It is a cyclic number.

It is not a de Polignac number, because 855543221 - 2²² = 851348917 is a prime.

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 (855543211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32905496 + ... + 32905521.

It is an arithmetic number, because the mean of its divisors is an integer number (230338563).

Almost surely, 2^855543221 is an apocalyptic number.

It is an amenable number.

855543221 is a deficient number, since it is larger than the sum of its proper divisors (65811031).

855543221 is a wasteful number, since it uses less digits than its factorization.

855543221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65811030.

The product of its digits is 48000, while the sum is 35.

The square root of 855543221 is about 29249.6704425879. The cubic root of 855543221 is about 949.3229602657.

Adding to 855543221 its reverse (122345558), we get a palindrome (977888779).

The spelling of 855543221 in words is "eight hundred fifty-five million, five hundred forty-three thousand, two hundred twenty-one".