12020100021 has 6 divisors (see below), whose sum is σ = 17362366710. Its totient is φ = 8013400008.

The previous prime is 12020100007. The next prime is 12020100041. The reversal of 12020100021 is 12000102021.

It can be written as a sum of positive squares in only one way, i.e., 11387024100 + 633075921 = 106710^2 + 25161^2 .

It is not a de Polignac number, because 12020100021 - 2⁷ = 12020099893 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 1335566669 = 12020100021 / (1 + 2 + 0 + 2 + 0 + 1 + 0 + 0 + 0 + 2 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 12020099976 and 12020100012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12020100041) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 667783326 + ... + 667783343.

It is an arithmetic number, because the mean of its divisors is an integer number (2893727785).

Almost surely, 2^12020100021 is an apocalyptic number.

It is an amenable number.

12020100021 is a deficient number, since it is larger than the sum of its proper divisors (5342266689).

12020100021 is a wasteful number, since it uses less digits than its factorization.

12020100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1335566675 (or 1335566672 counting only the distinct ones).

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

Adding to 12020100021 its reverse (12000102021), we get a palindrome (24020202042).

The spelling of 12020100021 in words is "twelve billion, twenty million, one hundred thousand, twenty-one".