12021139456 has 48 divisors (see below), whose sum is σ = 24490147500. Its totient is φ = 5897109504.

The previous prime is 12021139423. The next prime is 12021139463. The reversal of 12021139456 is 65493112021.

It can be written as a sum of positive squares in 2 ways, for example, as 10387686400 + 1633453056 = 101920^2 + 40416^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53170 + ... + 163918.

Almost surely, 2^12021139456 is an apocalyptic number.

12021139456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12021139456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12245073750).

12021139456 is an abundant number, since it is smaller than the sum of its proper divisors (12469008044).

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

12021139456 is an equidigital number, since it uses as much as digits as its factorization.

12021139456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110824 (or 110804 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 34.

The spelling of 12021139456 in words is "twelve billion, twenty-one million, one hundred thirty-nine thousand, four hundred fifty-six".