21225267 has 16 divisors (see below), whose sum is σ = 35937280. Its totient is φ = 12128616.

The previous prime is 21225263. The next prime is 21225277. The reversal of 21225267 is 76252212.

It is not a de Polignac number, because 21225267 - 2² = 21225263 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21225267.

It is not an unprimeable number, because it can be changed into a prime (21225263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55963 + ... + 56340.

It is an arithmetic number, because the mean of its divisors is an integer number (2246080).

Almost surely, 2^21225267 is an apocalyptic number.

21225267 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21225267 is a deficient number, since it is larger than the sum of its proper divisors (14712013).

21225267 is a wasteful number, since it uses less digits than its factorization.

21225267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112319 (or 112313 counting only the distinct ones).

The product of its digits is 3360, while the sum is 27.

The square root of 21225267 is about 4607.0887770912. The cubic root of 21225267 is about 276.8754104389.

Adding to 21225267 its reverse (76252212), we get a palindrome (97477479).

The spelling of 21225267 in words is "twenty-one million, two hundred twenty-five thousand, two hundred sixty-seven".