201220012121 has 4 divisors (see below), whose sum is σ = 204223295952. Its totient is φ = 198216728292.

The previous prime is 201220012111. The next prime is 201220012187. The reversal of 201220012121 is 121210022102.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201220012121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 201220012096 and 201220012105.

It is not an unprimeable number, because it can be changed into a prime (201220012111) 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, 1501641815 + ... + 1501641948.

It is an arithmetic number, because the mean of its divisors is an integer number (51055823988).

Almost surely, 2^201220012121 is an apocalyptic number.

It is an amenable number.

201220012121 is a deficient number, since it is larger than the sum of its proper divisors (3003283831).

201220012121 is an equidigital number, since it uses as much as digits as its factorization.

201220012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3003283830.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 201220012121 its reverse (121210022102), we get a palindrome (322430034223).

The spelling of 201220012121 in words is "two hundred one billion, two hundred twenty million, twelve thousand, one hundred twenty-one".