20102021021 has 8 divisors (see below), whose sum is σ = 20825393664.
Its totient is φ = 19383330960.
The previous prime is 20102020993. The next prime is 20102021029. The reversal of 20102021021 is 12012020102.
It is a happy number.
It is a sphenic number, since it is the product of 3 distinct primes.
It is a cyclic number.
It is not a de Polignac number, because 20102021021 - 210 = 20102019997 is a prime.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 20102020993 and 20102021011.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (20102021029) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1161905 + ... + 1179078.
It is an arithmetic number, because the mean of its divisors is an integer number (2603174208).
Almost surely, 220102021021 is an apocalyptic number.
It is an amenable number.
20102021021 is a deficient number, since it is larger than the sum of its proper divisors (723372643).
20102021021 is a wasteful number, since it uses less digits than its factorization.
20102021021 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 2341291.
The product of its (nonzero) digits is 16, while the sum is 11.
Adding to 20102021021 its reverse (12012020102), we get a palindrome (32114041123).
The spelling of 20102021021 in words is "twenty billion, one hundred two million, twenty-one thousand, twenty-one".