554216021 has 4 divisors (see below), whose sum is σ = 555151212. Its totient is φ = 553280832.

The previous prime is 554216009. The next prime is 554216029. The reversal of 554216021 is 120612455.

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 229855921 + 324360100 = 15161^2 + 18010^2 .

It is a cyclic number.

It is not a de Polignac number, because 554216021 - 2⁶ = 554215957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (554216029) 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, 466706 + ... + 467891.

It is an arithmetic number, because the mean of its divisors is an integer number (138787803).

Almost surely, 2^554216021 is an apocalyptic number.

It is an amenable number.

554216021 is a deficient number, since it is larger than the sum of its proper divisors (935191).

554216021 is an equidigital number, since it uses as much as digits as its factorization.

554216021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 935190.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 554216021 is about 23541.7930710471. The cubic root of 554216021 is about 821.4094444415.

Adding to 554216021 its reverse (120612455), we get a palindrome (674828476).

The spelling of 554216021 in words is "five hundred fifty-four million, two hundred sixteen thousand, twenty-one".