21340308 has 48 divisors (see below), whose sum is σ = 54613440. Its totient is φ = 6432000.

The previous prime is 21340289. The next prime is 21340313. The reversal of 21340308 is 80304312.

It is a happy number.

It is a congruent number.

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, 35208 + ... + 35808.

It is an arithmetic number, because the mean of its divisors is an integer number (1137780).

Almost surely, 2^21340308 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 21340308, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27306720).

21340308 is an abundant number, since it is smaller than the sum of its proper divisors (33273132).

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

21340308 is a wasteful number, since it uses less digits than its factorization.

21340308 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21340308 is about 4619.5571216297. The cubic root of 21340308 is about 277.3747312205.

The spelling of 21340308 in words is "twenty-one million, three hundred forty thousand, three hundred eight".