21352608 has 72 divisors (see below), whose sum is σ = 61248096. Its totient is φ = 7056000.

The previous prime is 21352601. The next prime is 21352609. The reversal of 21352608 is 80625312.

21352608 is a `hidden beast` number, since 2 + 1 + 3 + 52 + 608 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is not an unprimeable number, because it can be changed into a prime (21352601) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43243 + ... + 43733.

It is an arithmetic number, because the mean of its divisors is an integer number (850668).

Almost surely, 2^21352608 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 21352608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30624048).

21352608 is an abundant number, since it is smaller than the sum of its proper divisors (39895488).

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

21352608 is a wasteful number, since it uses less digits than its factorization.

21352608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658 (or 647 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 21352608 is about 4620.8882263045. Note that the first 3 decimals coincide. The cubic root of 21352608 is about 277.4280115189.

The spelling of 21352608 in words is "twenty-one million, three hundred fifty-two thousand, six hundred eight".