21205282 has 16 divisors (see below), whose sum is σ = 37239552. Its totient is φ = 8866080.

The previous prime is 21205279. The next prime is 21205291. The reversal of 21205282 is 28250212.

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, 17898 + ... + 19045.

It is an arithmetic number, because the mean of its divisors is an integer number (2327472).

Almost surely, 2^21205282 is an apocalyptic number.

21205282 is a deficient number, since it is larger than the sum of its proper divisors (16034270).

21205282 is a wasteful number, since it uses less digits than its factorization.

21205282 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36993.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 21205282 is about 4604.9193261120. The cubic root of 21205282 is about 276.7884842821.

Adding to 21205282 its reverse (28250212), we get a palindrome (49455494).

The spelling of 21205282 in words is "twenty-one million, two hundred five thousand, two hundred eighty-two".