21425241 has 8 divisors (see below), whose sum is σ = 28607040. Its totient is φ = 14263472.

The previous prime is 21425233. The next prime is 21425251. The reversal of 21425241 is 14252412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21425241 - 2³ = 21425233 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21425251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2301 + ... + 6938.

It is an arithmetic number, because the mean of its divisors is an integer number (3575880).

Almost surely, 2^21425241 is an apocalyptic number.

It is an amenable number.

21425241 is a deficient number, since it is larger than the sum of its proper divisors (7181799).

21425241 is an equidigital number, since it uses as much as digits as its factorization.

21425241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10015.

The product of its digits is 640, while the sum is 21.

The square root of 21425241 is about 4628.7407574847. The cubic root of 21425241 is about 277.7422217541.

Adding to 21425241 its reverse (14252412), we get a palindrome (35677653).

The spelling of 21425241 in words is "twenty-one million, four hundred twenty-five thousand, two hundred forty-one".