201221306 has 48 divisors (see below), whose sum is σ = 360364032. Its totient is φ = 83703840.

The previous prime is 201221291. The next prime is 201221309. The reversal of 201221306 is 603122102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201221309) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 525191 + ... + 525573.

It is an arithmetic number, because the mean of its divisors is an integer number (7507584).

Almost surely, 2^201221306 is an apocalyptic number.

201221306 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

201221306 is a deficient number, since it is larger than the sum of its proper divisors (159142726).

201221306 is a wasteful number, since it uses less digits than its factorization.

201221306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 587 (or 576 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 201221306 is about 14185.2495924464. The cubic root of 201221306 is about 585.9915062815.

Adding to 201221306 its reverse (603122102), we get a palindrome (804343408).

The spelling of 201221306 in words is "two hundred one million, two hundred twenty-one thousand, three hundred six".