21225403 has 2 divisors, whose sum is σ = 21225404. Its totient is φ = 21225402.

The previous prime is 21225397. The next prime is 21225431. The reversal of 21225403 is 30452212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21225403 - 2²¹ = 19128251 is a prime.

It is not a weakly prime, because it can be changed into another prime (21225473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612701 + 10612702.

It is an arithmetic number, because the mean of its divisors is an integer number (10612702).

Almost surely, 2^21225403 is an apocalyptic number.

21225403 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225403 is an equidigital number, since it uses as much as digits as its factorization.

21225403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 21225403 is about 4607.1035369308. The cubic root of 21225403 is about 276.8760017934.

Adding to 21225403 its reverse (30452212), we get a palindrome (51677615).

The spelling of 21225403 in words is "twenty-one million, two hundred twenty-five thousand, four hundred three".