12120030021 has 64 divisors (see below), whose sum is σ = 18627231744. Its totient is φ = 6938342400.

The previous prime is 12120029981. The next prime is 12120030047. The reversal of 12120030021 is 12003002121.

It is not a de Polignac number, because 12120030021 - 2⁷ = 12120029893 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12120029979 and 12120030006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12120030121) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 31644796 + ... + 31645178.

It is an arithmetic number, because the mean of its divisors is an integer number (291050496).

Almost surely, 2^12120030021 is an apocalyptic number.

12120030021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12120030021 is a deficient number, since it is larger than the sum of its proper divisors (6507201723).

12120030021 is a wasteful number, since it uses less digits than its factorization.

12120030021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 834.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 12120030021 its reverse (12003002121), we get a palindrome (24123032142).

The spelling of 12120030021 in words is "twelve billion, one hundred twenty million, thirty thousand, twenty-one".