21201316 has 6 divisors (see below), whose sum is σ = 37102310. Its totient is φ = 10600656.

The previous prime is 21201311. The next prime is 21201347. The reversal of 21201316 is 61310212.

It can be written as a sum of positive squares in only one way, i.e., 20738916 + 462400 = 4554^2 + 680^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21201316.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2650161 + ... + 2650168.

Almost surely, 2^21201316 is an apocalyptic number.

It is an amenable number.

21201316 is a deficient number, since it is larger than the sum of its proper divisors (15900994).

21201316 is a wasteful number, since it uses less digits than its factorization.

21201316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5300333 (or 5300331 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 21201316 is about 4604.4886795387. The cubic root of 21201316 is about 276.7712273934.

Adding to 21201316 its reverse (61310212), we get a palindrome (82511528).

The spelling of 21201316 in words is "twenty-one million, two hundred one thousand, three hundred sixteen".