12421921536 has 360 divisors, whose sum is σ = 39992290800. Its totient is φ = 3822059520.

The previous prime is 12421921529. The next prime is 12421921553. The reversal of 12421921536 is 63512912421.

12421921536 is a `hidden beast` number, since 12 + 4 + 21 + 92 + 1 + 536 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 12421921536.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 16152960 + ... + 16153728.

Almost surely, 2^12421921536 is an apocalyptic number.

12421921536 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 12421921536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19996145400).

12421921536 is an abundant number, since it is smaller than the sum of its proper divisors (27570369264).

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

12421921536 is an equidigital number, since it uses as much as digits as its factorization.

12421921536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 857 (or 834 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The spelling of 12421921536 in words is "twelve billion, four hundred twenty-one million, nine hundred twenty-one thousand, five hundred thirty-six".