2001220000121 has 4 divisors (see below), whose sum is σ = 2002940740752. Its totient is φ = 1999499259492.

The previous prime is 2001220000051. The next prime is 2001220000123. The reversal of 2001220000121 is 1210000221002.

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.

It is a cyclic number.

It is not a de Polignac number, because 2001220000121 - 2³⁴ = 1984040130937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2001220000123) 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, 860368571 + ... + 860370896.

It is an arithmetic number, because the mean of its divisors is an integer number (500735185188).

Almost surely, 2^{2001220000121} is an apocalyptic number.

It is an amenable number.

2001220000121 is a deficient number, since it is larger than the sum of its proper divisors (1720740631).

2001220000121 is a wasteful number, since it uses less digits than its factorization.

2001220000121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1720740630.

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

Adding to 2001220000121 its reverse (1210000221002), we get a palindrome (3211220221123).

The spelling of 2001220000121 in words is "two trillion, one billion, two hundred twenty million, one hundred twenty-one", and thus it is an aban number.