20021020 has 24 divisors (see below), whose sum is σ = 43495200. Its totient is φ = 7732032.

The previous prime is 20020943. The next prime is 20021021. The reversal of 20021020 is 2012002.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20020994 and 20021012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021021) 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, 16680 + ... + 17839.

It is an arithmetic number, because the mean of its divisors is an integer number (1812300).

Almost surely, 2^20021020 is an apocalyptic number.

20021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20021020 is an abundant number, since it is smaller than the sum of its proper divisors (23474180).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20021020 is a wasteful number, since it uses less digits than its factorization.

20021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34557 (or 34555 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 7.

The square root of 20021020 is about 4474.4854452775. The cubic root of 20021020 is about 271.5368234611.

Adding to 20021020 its reverse (2012002), we get a palindrome (22033022).

The spelling of 20021020 in words is "twenty million, twenty-one thousand, twenty".