21425446 has 12 divisors (see below), whose sum is σ = 37385388. Its totient is φ = 9182292.

The previous prime is 21425431. The next prime is 21425471. The reversal of 21425446 is 64452412.

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 109216 + ... + 109411.

It is an arithmetic number, because the mean of its divisors is an integer number (3115449).

Almost surely, 2^21425446 is an apocalyptic number.

21425446 is a deficient number, since it is larger than the sum of its proper divisors (15959942).

21425446 is a wasteful number, since it uses less digits than its factorization.

21425446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218643 (or 218636 counting only the distinct ones).

The product of its digits is 7680, while the sum is 28.

The square root of 21425446 is about 4628.7629016833. The cubic root of 21425446 is about 277.7431075781.

Adding to 21425446 its reverse (64452412), we get a palindrome (85877858).

The spelling of 21425446 in words is "twenty-one million, four hundred twenty-five thousand, four hundred forty-six".