21225263 has 2 divisors, whose sum is σ = 21225264. Its totient is φ = 21225262.

The previous prime is 21225233. The next prime is 21225277. The reversal of 21225263 is 36252212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21225263 - 2¹⁴ = 21208879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21225203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612631 + 10612632.

It is an arithmetic number, because the mean of its divisors is an integer number (10612632).

Almost surely, 2^21225263 is an apocalyptic number.

21225263 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225263 is an equidigital number, since it uses as much as digits as its factorization.

21225263 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 23.

The square root of 21225263 is about 4607.0883429776. The cubic root of 21225263 is about 276.8753930460.

Adding to 21225263 its reverse (36252212), we get a palindrome (57477475).

The spelling of 21225263 in words is "twenty-one million, two hundred twenty-five thousand, two hundred sixty-three".