505216507221 has 12 divisors (see below), whose sum is σ = 729782275872. Its totient is φ = 336799420776.

The previous prime is 505216507217. The next prime is 505216507267. The reversal of 505216507221 is 122705612505.

505216507221 is a `hidden beast` number, since 5 + 0 + 521 + 65 + 0 + 72 + 2 + 1 = 666.

It is not a de Polignac number, because 505216507221 - 2² = 505216507217 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505216507121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 684831 + ... + 1216316.

It is an arithmetic number, because the mean of its divisors is an integer number (60815189656).

Almost surely, 2^505216507221 is an apocalyptic number.

It is an amenable number.

505216507221 is a deficient number, since it is larger than the sum of its proper divisors (224565768651).

505216507221 is a wasteful number, since it uses less digits than its factorization.

505216507221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1930680 (or 1930677 counting only the distinct ones).

The product of its (nonzero) digits is 42000, while the sum is 36.

The spelling of 505216507221 in words is "five hundred five billion, two hundred sixteen million, five hundred seven thousand, two hundred twenty-one".