2001011122121 has 6 divisors (see below), whose sum is σ = 2199458506266. Its totient is φ = 1819101020000.

The previous prime is 2001011122067. The next prime is 2001011122139. The reversal of 2001011122121 is 1212211101002.

It can be written as a sum of positive squares in only one way, i.e., 1470735882121 + 530275240000 = 1212739^2 + 728200^2 .

It is not a de Polignac number, because 2001011122121 - 2³⁰ = 1999937380297 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001011122096 and 2001011122105.

It is not an unprimeable number, because it can be changed into a prime (2001011122141) 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, 8268640880 + ... + 8268641121.

It is an arithmetic number, because the mean of its divisors is an integer number (366576417711).

Almost surely, 2^{2001011122121} is an apocalyptic number.

It is an amenable number.

2001011122121 is a deficient number, since it is larger than the sum of its proper divisors (198447384145).

2001011122121 is a wasteful number, since it uses less digits than its factorization.

2001011122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16537282023 (or 16537282012 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 2001011122121 its reverse (1212211101002), we get a palindrome (3213222223123).

The spelling of 2001011122121 in words is "two trillion, one billion, eleven million, one hundred twenty-two thousand, one hundred twenty-one".