20001121001 has 32 divisors (see below), whose sum is σ = 21559633920. Its totient is φ = 18500832000.

The previous prime is 20001120977. The next prime is 20001121031. The reversal of 20001121001 is 10012110002.

It is not a de Polignac number, because 20001121001 - 2¹⁰ = 20001119977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20001121001.

It is not an unprimeable number, because it can be changed into a prime (20001121031) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72206075 + ... + 72206351.

It is an arithmetic number, because the mean of its divisors is an integer number (673738560).

Almost surely, 2^20001121001 is an apocalyptic number.

It is an amenable number.

20001121001 is a deficient number, since it is larger than the sum of its proper divisors (1558512919).

20001121001 is a wasteful number, since it uses less digits than its factorization.

20001121001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 785.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 20001121001 its reverse (10012110002), we get a palindrome (30013231003).

The spelling of 20001121001 in words is "twenty billion, one million, one hundred twenty-one thousand, one".