21424574 has 16 divisors (see below), whose sum is σ = 33127488. Its totient is φ = 10386432.

The previous prime is 21424549. The next prime is 21424577. The reversal of 21424574 is 47542412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21424577) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9614 + ... + 11630.

It is an arithmetic number, because the mean of its divisors is an integer number (2070468).

Almost surely, 2^21424574 is an apocalyptic number.

21424574 is a deficient number, since it is larger than the sum of its proper divisors (11702914).

21424574 is a wasteful number, since it uses less digits than its factorization.

21424574 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2179.

The product of its digits is 8960, while the sum is 29.

The square root of 21424574 is about 4628.6687070906. The cubic root of 21424574 is about 277.7393395464.

Adding to 21424574 its reverse (47542412), we get a palindrome (68966986).

The spelling of 21424574 in words is "twenty-one million, four hundred twenty-four thousand, five hundred seventy-four".