20001121021 has 8 divisors (see below), whose sum is σ = 22912722944. Its totient is φ = 17103093840.

The previous prime is 20001120977. The next prime is 20001121031. The reversal of 20001121021 is 12012110002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20001121021 - 2²³ = 19992732413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20001120989 and 20001121007.

It is a congruent number.

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

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3390525 + ... + 3396418.

It is an arithmetic number, because the mean of its divisors is an integer number (2864090368).

Almost surely, 2^20001121021 is an apocalyptic number.

It is an amenable number.

20001121021 is a deficient number, since it is larger than the sum of its proper divisors (2911601923).

20001121021 is an equidigital number, since it uses as much as digits as its factorization.

20001121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6787371.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20001121021 its reverse (12012110002), we get a palindrome (32013231023).

The spelling of 20001121021 in words is "twenty billion, one million, one hundred twenty-one thousand, twenty-one".