201220121 has 4 divisors (see below), whose sum is σ = 201633792. Its totient is φ = 200806452.

The previous prime is 201220073. The next prime is 201220199. The reversal of 201220121 is 121022102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 121022102 = 2 ⋅60511051.

It is a cyclic number.

It is not a de Polignac number, because 201220121 - 2⁶ = 201220057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201220321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206105 + ... + 207078.

It is an arithmetic number, because the mean of its divisors is an integer number (50408448).

Almost surely, 2^201220121 is an apocalyptic number.

It is an amenable number.

201220121 is a deficient number, since it is larger than the sum of its proper divisors (413671).

201220121 is an equidigital number, since it uses as much as digits as its factorization.

201220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 413670.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 201220121 is about 14185.2078236450. The cubic root of 201220121 is about 585.9903559705.

Adding to 201220121 its reverse (121022102), we get a palindrome (322242223).

The spelling of 201220121 in words is "two hundred one million, two hundred twenty thousand, one hundred twenty-one".