201221312243 has 16 divisors (see below), whose sum is σ = 249157370880. Its totient is φ = 158554682496.

The previous prime is 201221312153. The next prime is 201221312267. The reversal of 201221312243 is 342213122102.

It is not a de Polignac number, because 201221312243 - 2³⁴ = 184041443059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201221312293) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19656923 + ... + 19667156.

It is an arithmetic number, because the mean of its divisors is an integer number (15572335680).

Almost surely, 2^201221312243 is an apocalyptic number.

201221312243 is a deficient number, since it is larger than the sum of its proper divisors (47936058637).

201221312243 is a wasteful number, since it uses less digits than its factorization.

201221312243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39324146.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 201221312243 its reverse (342213122102), we get a palindrome (543434434345).

The spelling of 201221312243 in words is "two hundred one billion, two hundred twenty-one million, three hundred twelve thousand, two hundred forty-three".