20021000010121 has 6 divisors (see below), whose sum is σ = 22006553730266. Its totient is φ = 18200909100000.

The previous prime is 20021000010119. The next prime is 20021000010131. The reversal of 20021000010121 is 12101000012002.

It can be written as a sum of positive squares in only one way, i.e., 12180658406400 + 7840341603721 = 3490080^2 + 2800061^2 .

It is not a de Polignac number, because 20021000010121 - 2¹ = 20021000010119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20021000010098 and 20021000010107.

It is not an unprimeable number, because it can be changed into a prime (20021000010131) 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, 82731404880 + ... + 82731405121.

Almost surely, 2^{20021000010121} is an apocalyptic number.

It is an amenable number.

20021000010121 is a deficient number, since it is larger than the sum of its proper divisors (1985553720145).

20021000010121 is a wasteful number, since it uses less digits than its factorization.

20021000010121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165462810023 (or 165462810012 counting only the distinct ones).

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

Adding to 20021000010121 its reverse (12101000012002), we get a palindrome (32122000022123).

The spelling of 20021000010121 in words is "twenty trillion, twenty-one billion, ten thousand, one hundred twenty-one".