21603272 has 16 divisors (see below), whose sum is σ = 41171100. Its totient is φ = 10624320.

The previous prime is 21603271. The next prime is 21603293. The reversal of 21603272 is 27230612.

It can be written as a sum of positive squares in 2 ways, for example, as 21585316 + 17956 = 4646^2 + 134^2 .

It is a super-2 number, since 2×21603272² = 933402722211968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21603271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21647 + ... + 22622.

Almost surely, 2^21603272 is an apocalyptic number.

It is an amenable number.

21603272 is a deficient number, since it is larger than the sum of its proper divisors (19567828).

21603272 is a wasteful number, since it uses less digits than its factorization.

21603272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44336 (or 44332 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 21603272 is about 4647.9320132721. The cubic root of 21603272 is about 278.5093916018.

Adding to 21603272 its reverse (27230612), we get a palindrome (48833884).

The spelling of 21603272 in words is "twenty-one million, six hundred three thousand, two hundred seventy-two".