555642121 has 4 divisors (see below), whose sum is σ = 557216532. Its totient is φ = 554067712.

The previous prime is 555642103. The next prime is 555642149. The reversal of 555642121 is 121246555.

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 299290000 + 256352121 = 17300^2 + 16011^2 .

It is a cyclic number.

It is not a de Polignac number, because 555642121 - 2²⁹ = 18771209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (555642221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 786676 + ... + 787381.

It is an arithmetic number, because the mean of its divisors is an integer number (139304133).

Almost surely, 2^555642121 is an apocalyptic number.

It is an amenable number.

555642121 is a deficient number, since it is larger than the sum of its proper divisors (1574411).

555642121 is a wasteful number, since it uses less digits than its factorization.

555642121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1574410.

The product of its digits is 12000, while the sum is 31.

The square root of 555642121 is about 23572.0622984074. The cubic root of 555642121 is about 822.1133869749.

Adding to 555642121 its reverse (121246555), we get a palindrome (676888676).

The spelling of 555642121 in words is "five hundred fifty-five million, six hundred forty-two thousand, one hundred twenty-one".