21424535 has 16 divisors (see below), whose sum is σ = 28702080. Its totient is φ = 15217440.

The previous prime is 21424511. The next prime is 21424547. The reversal of 21424535 is 53542412.

It is a happy number.

It is not a de Polignac number, because 21424535 - 2¹² = 21420439 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2165 + ... + 6894.

It is an arithmetic number, because the mean of its divisors is an integer number (1793880).

Almost surely, 2^21424535 is an apocalyptic number.

21424535 is a deficient number, since it is larger than the sum of its proper divisors (7277545).

21424535 is a wasteful number, since it uses less digits than its factorization.

21424535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9118.

The product of its digits is 4800, while the sum is 26.

The square root of 21424535 is about 4628.6644942143. The cubic root of 21424535 is about 277.7391710197.

Adding to 21424535 its reverse (53542412), we get a palindrome (74966947).

The spelling of 21424535 in words is "twenty-one million, four hundred twenty-four thousand, five hundred thirty-five".