21270508 has 36 divisors (see below), whose sum is σ = 44241120. Its totient is φ = 8918112.

The previous prime is 21270439. The next prime is 21270511. The reversal of 21270508 is 80507212.

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 11 ways as a sum of consecutive naturals, for example, 8058 + ... + 10366.

It is an arithmetic number, because the mean of its divisors is an integer number (1228920).

Almost surely, 2^21270508 is an apocalyptic number.

21270508 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21270508, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22120560).

21270508 is an abundant number, since it is smaller than the sum of its proper divisors (22970612).

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

21270508 is a wasteful number, since it uses less digits than its factorization.

21270508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2374 (or 2365 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 21270508 is about 4611.9960971362. The cubic root of 21270508 is about 277.0719879627.

The spelling of 21270508 in words is "twenty-one million, two hundred seventy thousand, five hundred eight".