21200272 has 10 divisors (see below), whose sum is σ = 41075558. Its totient is φ = 10600128.

The previous prime is 21200233. The next prime is 21200279. The reversal of 21200272 is 27200212.

It can be written as a sum of positive squares in only one way, i.e., 11861136 + 9339136 = 3444^2 + 3056^2 .

It is a Harshad number since it is a multiple of its sum of digits (16), and also a Moran number because the ratio is a prime number: 1325017 = 21200272 / (2 + 1 + 2 + 0 + 0 + 2 + 7 + 2).

It is not an unprimeable number, because it can be changed into a prime (21200279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 662493 + ... + 662524.

Almost surely, 2^21200272 is an apocalyptic number.

It is an amenable number.

21200272 is a deficient number, since it is larger than the sum of its proper divisors (19875286).

21200272 is a wasteful number, since it uses less digits than its factorization.

21200272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1325025 (or 1325019 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 21200272 is about 4604.3753105063. The cubic root of 21200272 is about 276.7666843750.

Adding to 21200272 its reverse (27200212), we get a palindrome (48400484).

The spelling of 21200272 in words is "twenty-one million, two hundred thousand, two hundred seventy-two".