21227716 has 6 divisors (see below), whose sum is σ = 37148510. Its totient is φ = 10613856.

The previous prime is 21227711. The next prime is 21227753. The reversal of 21227716 is 61772212.

It can be written as a sum of positive squares in only one way, i.e., 14745600 + 6482116 = 3840^2 + 2546^2 .

It is a super-3 number, since 3×21227716³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21227711) 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 as a sum of consecutive naturals, namely, 2653461 + ... + 2653468.

Almost surely, 2^21227716 is an apocalyptic number.

It is an amenable number.

21227716 is a deficient number, since it is larger than the sum of its proper divisors (15920794).

21227716 is a wasteful number, since it uses less digits than its factorization.

21227716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5306933 (or 5306931 counting only the distinct ones).

The product of its digits is 2352, while the sum is 28.

The square root of 21227716 is about 4607.3545554906. The cubic root of 21227716 is about 276.8860587824.

Adding to 21227716 its reverse (61772212), we get a palindrome (82999928).

The spelling of 21227716 in words is "twenty-one million, two hundred twenty-seven thousand, seven hundred sixteen".