21463225 has 24 divisors (see below), whose sum is σ = 31049600. Its totient is φ = 14711760.

The previous prime is 21463223. The next prime is 21463271. The reversal of 21463225 is 52236412.

It is not a de Polignac number, because 21463225 - 2¹ = 21463223 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 21463225.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21463223) 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 23 ways as a sum of consecutive naturals, for example, 7324 + ... + 9826.

Almost surely, 2^21463225 is an apocalyptic number.

21463225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21463225 is a deficient number, since it is larger than the sum of its proper divisors (9586375).

21463225 is an equidigital number, since it uses as much as digits as its factorization.

21463225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2534 (or 2515 counting only the distinct ones).

The product of its digits is 2880, while the sum is 25.

The square root of 21463225 is about 4632.8420003277. The cubic root of 21463225 is about 277.9062577505.

Adding to 21463225 its reverse (52236412), we get a palindrome (73699637).

The spelling of 21463225 in words is "twenty-one million, four hundred sixty-three thousand, two hundred twenty-five".