201221123 has 6 divisors (see below), whose sum is σ = 206011404. Its totient is φ = 196539756.

The previous prime is 201221113. The next prime is 201221143. The reversal of 201221123 is 321122102.

It is a happy number.

It is not a de Polignac number, because 201221123 - 2¹⁴ = 201204739 is a prime.

It is a super-2 number, since 2×201221123² = 80979880682762258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201221098 and 201221107.

It is not an unprimeable number, because it can be changed into a prime (201221113) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 52565 + ... + 56262.

It is an arithmetic number, because the mean of its divisors is an integer number (34335234).

Almost surely, 2^201221123 is an apocalyptic number.

201221123 is a deficient number, since it is larger than the sum of its proper divisors (4790281).

201221123 is an equidigital number, since it uses as much as digits as its factorization.

201221123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108913 (or 108870 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 201221123 is about 14185.2431420825. The cubic root of 201221123 is about 585.9913286389.

Adding to 201221123 its reverse (321122102), we get a palindrome (522343225).

The spelling of 201221123 in words is "two hundred one million, two hundred twenty-one thousand, one hundred twenty-three".