2020020021 has 12 divisors (see below), whose sum is σ = 2988973260. Its totient is φ = 1313833920.

The previous prime is 2020019999. The next prime is 2020020029. The reversal of 2020020021 is 1200200202.

It can be written as a sum of positive squares in 2 ways, for example, as 57972996 + 1962047025 = 7614^2 + 44295^2 .

It is not a de Polignac number, because 2020020021 - 2⁶ = 2020019957 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 2020019985 and 2020020012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2020020029) 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 11 ways as a sum of consecutive naturals, for example, 2736786 + ... + 2737523.

It is an arithmetic number, because the mean of its divisors is an integer number (249081105).

Almost surely, 2^2020020021 is an apocalyptic number.

It is an amenable number.

2020020021 is a deficient number, since it is larger than the sum of its proper divisors (968953239).

2020020021 is a wasteful number, since it uses less digits than its factorization.

2020020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5474356 (or 5474353 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 2020020021 is about 44944.6328386383. The cubic root of 2020020021 is about 1264.1110411999. Note that the first 3 decimals are identical.

Adding to 2020020021 its reverse (1200200202), we get a palindrome (3220220223).

The spelling of 2020020021 in words is "two billion, twenty million, twenty thousand, twenty-one".