21203282 has 4 divisors (see below), whose sum is σ = 31804926. Its totient is φ = 10601640.

The previous prime is 21203279. The next prime is 21203291. The reversal of 21203282 is 28230212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18241441 + 2961841 = 4271^2 + 1721^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5300819 + ... + 5300822.

Almost surely, 2^21203282 is an apocalyptic number.

21203282 is a deficient number, since it is larger than the sum of its proper divisors (10601644).

21203282 is a wasteful number, since it uses less digits than its factorization.

21203282 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10601643.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 21203282 is about 4604.7021619210. The cubic root of 21203282 is about 276.7797821362.

Adding to 21203282 its reverse (28230212), we get a palindrome (49433494).

The spelling of 21203282 in words is "twenty-one million, two hundred three thousand, two hundred eighty-two".