21424146 has 16 divisors (see below), whose sum is σ = 42895008. Its totient is φ = 7133600.

The previous prime is 21424129. The next prime is 21424159. The reversal of 21424146 is 64142412.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7681 + ... + 10091.

It is an arithmetic number, because the mean of its divisors is an integer number (2680938).

Almost surely, 2^21424146 is an apocalyptic number.

21424146 is an abundant number, since it is smaller than the sum of its proper divisors (21470862).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21424146 is a wasteful number, since it uses less digits than its factorization.

21424146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3897.

The product of its digits is 1536, while the sum is 24.

The square root of 21424146 is about 4628.6224732635. The cubic root of 21424146 is about 277.7374900623.

Adding to 21424146 its reverse (64142412), we get a palindrome (85566558).

The spelling of 21424146 in words is "twenty-one million, four hundred twenty-four thousand, one hundred forty-six".