21359616 has 88 divisors (see below), whose sum is σ = 60427440. Its totient is φ = 6684672.

The previous prime is 21359603. The next prime is 21359621. The reversal of 21359616 is 61695312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52020 + ... + 52428.

Almost surely, 2^21359616 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 21359616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30213720).

21359616 is an abundant number, since it is smaller than the sum of its proper divisors (39067824).

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

21359616 is a wasteful number, since it uses less digits than its factorization.

21359616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449 (or 431 counting only the distinct ones).

The product of its digits is 9720, while the sum is 33.

The square root of 21359616 is about 4621.6464598669. The cubic root of 21359616 is about 277.4583591442.

The spelling of 21359616 in words is "twenty-one million, three hundred fifty-nine thousand, six hundred sixteen".