20010121021 has 24 divisors (see below), whose sum is σ = 22235012352. Its totient is φ = 17992867200.

The previous prime is 20010121013. The next prime is 20010121063. The reversal of 20010121021 is 12012101002.

It is not a de Polignac number, because 20010121021 - 2³ = 20010121013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20010120989 and 20010121007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20010121081) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8298306 + ... + 8300716.

It is an arithmetic number, because the mean of its divisors is an integer number (926458848).

Almost surely, 2^20010121021 is an apocalyptic number.

It is an amenable number.

20010121021 is a deficient number, since it is larger than the sum of its proper divisors (2224891331).

20010121021 is a wasteful number, since it uses less digits than its factorization.

20010121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3153 (or 3142 counting only the distinct ones).

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

Adding to 20010121021 its reverse (12012101002), we get a palindrome (32022222023).

It can be divided in two parts, 200101 and 21021, that added together give a palindrome (221122).

The spelling of 20010121021 in words is "twenty billion, ten million, one hundred twenty-one thousand, twenty-one".