555066221 has 4 divisors (see below), whose sum is σ = 555137244. Its totient is φ = 554995200.

The previous prime is 555066203. The next prime is 555066227. The reversal of 555066221 is 122660555.

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 157502500 + 397563721 = 12550^2 + 19939^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-555066221 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 (555066227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22100 + ... + 39981.

It is an arithmetic number, because the mean of its divisors is an integer number (138784311).

Almost surely, 2^555066221 is an apocalyptic number.

It is an amenable number.

555066221 is a deficient number, since it is larger than the sum of its proper divisors (71023).

555066221 is an equidigital number, since it uses as much as digits as its factorization.

555066221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71022.

The product of its (nonzero) digits is 18000, while the sum is 32.

The square root of 555066221 is about 23559.8433993098. The cubic root of 555066221 is about 821.8292599873.

The spelling of 555066221 in words is "five hundred fifty-five million, sixty-six thousand, two hundred twenty-one".