21393696 has 96 divisors (see below), whose sum is σ = 60903360. Its totient is φ = 6552576.

The previous prime is 21393683. The next prime is 21393707. The reversal of 21393696 is 69639312.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67330 + ... + 67646.

It is an arithmetic number, because the mean of its divisors is an integer number (634410).

Almost surely, 2^21393696 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 21393696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30451680).

21393696 is an abundant number, since it is smaller than the sum of its proper divisors (39509664).

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

21393696 is a wasteful number, since it uses less digits than its factorization.

21393696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386 (or 378 counting only the distinct ones).

The product of its digits is 52488, while the sum is 39.

The square root of 21393696 is about 4625.3319880847. The cubic root of 21393696 is about 277.6058455086.

The spelling of 21393696 in words is "twenty-one million, three hundred ninety-three thousand, six hundred ninety-six".