221211257066720 has 24 divisors (see below), whose sum is σ = 522611594820504. Its totient is φ = 88484502826624.

The previous prime is 221211257066671. The next prime is 221211257066731. The reversal of 221211257066720 is 27660752112122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 691285178174 + ... + 691285178493.

It is an arithmetic number, because the mean of its divisors is an integer number (21775483117521).

Almost surely, 2^{221211257066720} is an apocalyptic number.

221211257066720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221211257066720 is an abundant number, since it is smaller than the sum of its proper divisors (301400337753784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221211257066720 is a wasteful number, since it uses less digits than its factorization.

221211257066720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1382570356682 (or 1382570356674 counting only the distinct ones).

The product of its (nonzero) digits is 282240, while the sum is 44.

The spelling of 221211257066720 in words is "two hundred twenty-one trillion, two hundred eleven billion, two hundred fifty-seven million, sixty-six thousand, seven hundred twenty".