21606346412 has 48 divisors (see below), whose sum is σ = 44739582720. Its totient is φ = 8933198400.

The previous prime is 21606346387. The next prime is 21606346417. The reversal of 21606346412 is 21464360612.

It is not an unprimeable number, because it can be changed into a prime (21606346417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1037987 + ... + 1058597.

It is an arithmetic number, because the mean of its divisors is an integer number (932074640).

Almost surely, 2^21606346412 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21606346412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22369791360).

21606346412 is an abundant number, since it is smaller than the sum of its proper divisors (23133236308).

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

21606346412 is a wasteful number, since it uses less digits than its factorization.

21606346412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21942 (or 21940 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 35.

The spelling of 21606346412 in words is "twenty-one billion, six hundred six million, three hundred forty-six thousand, four hundred twelve".