1020020021 has 16 divisors (see below), whose sum is σ = 1049857536. Its totient is φ = 990734976.

The previous prime is 1020019969. The next prime is 1020020041. The reversal of 1020020021 is 1200200201.

1020020021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1020020021 - 2¹⁴ = 1020003637 is a prime.

It is a super-4 number, since 4×1020020021⁴ (a number of 37 digits) contains 4444 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1020019990 and 1020020008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020020041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2202836 + ... + 2203298.

It is an arithmetic number, because the mean of its divisors is an integer number (65616096).

Almost surely, 2^1020020021 is an apocalyptic number.

It is an amenable number.

1020020021 is a deficient number, since it is larger than the sum of its proper divisors (29837515).

1020020021 is a wasteful number, since it uses less digits than its factorization.

1020020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 932.

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

The square root of 1020020021 is about 31937.7522847178. The cubic root of 1020020021 is about 1006.6292956586.

Adding to 1020020021 its reverse (1200200201), we get a palindrome (2220220222).

The spelling of 1020020021 in words is "one billion, twenty million, twenty thousand, twenty-one".