12100021020 has 72 divisors (see below), whose sum is σ = 36821584800. Its totient is φ = 3216282240.

The previous prime is 12100021019. The next prime is 12100021027. The reversal of 12100021020 is 2012000121.

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 = 12100020993 and 12100021011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12100021027) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52095 + ... + 164054.

It is an arithmetic number, because the mean of its divisors is an integer number (511410900).

Almost surely, 2^12100021020 is an apocalyptic number.

12100021020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12100021020 is an abundant number, since it is smaller than the sum of its proper divisors (24721563780).

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

12100021020 is a wasteful number, since it uses less digits than its factorization.

12100021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216475 (or 216470 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 12100021020 its reverse (2012000121), we get a palindrome (14112021141).

The spelling of 12100021020 in words is "twelve billion, one hundred million, twenty-one thousand, twenty".