21730848 has 48 divisors (see below), whose sum is σ = 58133376. Its totient is φ = 7105280.

The previous prime is 21730829. The next prime is 21730853. The reversal of 21730848 is 84803712.

It is a tau number, because it is divible by the number of its divisors (48).

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, 2953 + ... + 7223.

It is an arithmetic number, because the mean of its divisors is an integer number (1211112).

Almost surely, 2^21730848 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 21730848, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29066688).

21730848 is an abundant number, since it is smaller than the sum of its proper divisors (36402528).

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

21730848 is a wasteful number, since it uses less digits than its factorization.

21730848 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4337 (or 4329 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 21730848 is about 4661.6357644072. The cubic root of 21730848 is about 279.0565525577.

It can be divided in two parts, 21730 and 848, that added together give a triangular number (22578 = T₂₁₂).

The spelling of 21730848 in words is "twenty-one million, seven hundred thirty thousand, eight hundred forty-eight".