2556433221 has 4 divisors (see below), whose sum is σ = 3408577632. Its totient is φ = 1704288812.

The previous prime is 2556433199. The next prime is 2556433237. The reversal of 2556433221 is 1223346552.

It is a happy number.

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 2556433221 - 2¹⁹ = 2555908933 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2556433921) 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 3 ways as a sum of consecutive naturals, for example, 426072201 + ... + 426072206.

It is an arithmetic number, because the mean of its divisors is an integer number (852144408).

Almost surely, 2^2556433221 is an apocalyptic number.

It is an amenable number.

2556433221 is a deficient number, since it is larger than the sum of its proper divisors (852144411).

2556433221 is an equidigital number, since it uses as much as digits as its factorization.

2556433221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 852144410.

The product of its digits is 43200, while the sum is 33.

The square root of 2556433221 is about 50561.1829470000. The cubic root of 2556433221 is about 1367.3451384804.

Adding to 2556433221 its reverse (1223346552), we get a palindrome (3779779773).

It can be divided in two parts, 25564 and 33221, that added together give a palindrome (58785).

The spelling of 2556433221 in words is "two billion, five hundred fifty-six million, four hundred thirty-three thousand, two hundred twenty-one".