20210120020 has 24 divisors (see below), whose sum is σ = 43588314504. Its totient is φ = 7865559936.

The previous prime is 20210120009. The next prime is 20210120027. The reversal of 20210120020 is 2002101202.

It can be written as a sum of positive squares in 4 ways, for example, as 5075707536 + 15134412484 = 71244^2 + 123022^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 20210119979 and 20210120006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20210120027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13654747 + ... + 13656226.

It is an arithmetic number, because the mean of its divisors is an integer number (1816179771).

Almost surely, 2^20210120020 is an apocalyptic number.

20210120020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20210120020 is an abundant number, since it is smaller than the sum of its proper divisors (23378194484).

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

20210120020 is a wasteful number, since it uses less digits than its factorization.

20210120020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27311019 (or 27311017 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 20210120020 its reverse (2002101202), we get a palindrome (22212221222).

The spelling of 20210120020 in words is "twenty billion, two hundred ten million, one hundred twenty thousand, twenty".