21468656 has 40 divisors (see below), whose sum is σ = 45663744. Its totient is φ = 9696960.

The previous prime is 21468649. The next prime is 21468659. The reversal of 21468656 is 65686412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21468659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38975 + ... + 39521.

Almost surely, 2^21468656 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 21468656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22831872).

21468656 is an abundant number, since it is smaller than the sum of its proper divisors (24195088).

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

21468656 is a wasteful number, since it uses less digits than its factorization.

21468656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 789 (or 783 counting only the distinct ones).

The product of its digits is 69120, while the sum is 38.

The square root of 21468656 is about 4633.4281045464. The cubic root of 21468656 is about 277.9296960051.

The spelling of 21468656 in words is "twenty-one million, four hundred sixty-eight thousand, six hundred fifty-six".