555421 has 2 divisors, whose sum is σ = 555422. Its totient is φ = 555420.

The previous prime is 555419. The next prime is 555439. The reversal of 555421 is 124555.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 319225 + 236196 = 565^2 + 486^2 .

It is a cyclic number.

It is not a de Polignac number, because 555421 - 2¹ = 555419 is a prime.

Together with 555419, it forms a pair of twin primes.

555421 is a lucky number.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 555392 and 555401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (555461) 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 as a sum of consecutive naturals, namely, 277710 + 277711.

It is an arithmetic number, because the mean of its divisors is an integer number (277711).

2⁵⁵⁵⁴²¹ is an apocalyptic number.

It is an amenable number.

555421 is a deficient number, since it is larger than the sum of its proper divisors (1).

555421 is an equidigital number, since it uses as much as digits as its factorization.

555421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1000, while the sum is 22.

The square root of 555421 is about 745.2657244232. The cubic root of 555421 is about 82.2004317577.

Adding to 555421 its reverse (124555), we get a palindrome (679976).

It can be divided in two parts, 55 and 5421, that added together give a square (5476 = 74²).

The spelling of 555421 in words is "five hundred fifty-five thousand, four hundred twenty-one".