20121021020 has 24 divisors (see below), whose sum is σ = 42763233744. Its totient is φ = 7951438976.

The previous prime is 20121021001. The next prime is 20121021031. The reversal of 20121021020 is 2012012102.

It is a happy number.

It is a super-4 number, since 4×20121021020⁴ (a number of 42 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20121020992 and 20121021010.

It is a congruent number.

It is an unprimeable number.

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, 6058889 + ... + 6062208.

It is an arithmetic number, because the mean of its divisors is an integer number (1781801406).

Almost surely, 2^20121021020 is an apocalyptic number.

20121021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121021020 is an abundant number, since it is smaller than the sum of its proper divisors (22642212724).

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

20121021020 is a wasteful number, since it uses less digits than its factorization.

20121021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12121189 (or 12121187 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 20121021020 its reverse (2012012102), we get a palindrome (22133033122).

The spelling of 20121021020 in words is "twenty billion, one hundred twenty-one million, twenty-one thousand, twenty".