21703968 has 288 divisors, whose sum is σ = 79252992. Its totient is φ = 5529600.

The previous prime is 21703967. The next prime is 21703993. The reversal of 21703968 is 86930712.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is not an unprimeable number, because it can be changed into a prime (21703967) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 700113 + ... + 700143.

It is an arithmetic number, because the mean of its divisors is an integer number (275184).

Almost surely, 2^21703968 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 21703968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39626496).

21703968 is an abundant number, since it is smaller than the sum of its proper divisors (57549024).

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

21703968 is a wasteful number, since it uses less digits than its factorization.

21703968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 21703968 is about 4658.7517641531. The cubic root of 21703968 is about 278.9414452984.

The spelling of 21703968 in words is "twenty-one million, seven hundred three thousand, nine hundred sixty-eight".