21748308 has 12 divisors (see below), whose sum is σ = 50746080. Its totient is φ = 7249432.

The previous prime is 21748297. The next prime is 21748313. The reversal of 21748308 is 80384712.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 906168 + ... + 906191.

It is an arithmetic number, because the mean of its divisors is an integer number (4228840).

Almost surely, 2^21748308 is an apocalyptic number.

It is an amenable number.

21748308 is an abundant number, since it is smaller than the sum of its proper divisors (28997772).

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

21748308 is a wasteful number, since it uses less digits than its factorization.

21748308 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1812366 (or 1812364 counting only the distinct ones).

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

The square root of 21748308 is about 4663.5081215754. The cubic root of 21748308 is about 279.1312700449.

The spelling of 21748308 in words is "twenty-one million, seven hundred forty-eight thousand, three hundred eight".