21424134 has 16 divisors (see below), whose sum is σ = 45103680. Its totient is φ = 6765480.

The previous prime is 21424129. The next prime is 21424159. The reversal of 21424134 is 43142412.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21424134.

It is a congruent 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, 93852 + ... + 94079.

It is an arithmetic number, because the mean of its divisors is an integer number (2818980).

Almost surely, 2^21424134 is an apocalyptic number.

21424134 is an abundant number, since it is smaller than the sum of its proper divisors (23679546).

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

21424134 is a wasteful number, since it uses less digits than its factorization.

21424134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187955.

The product of its digits is 768, while the sum is 21.

The square root of 21424134 is about 4628.6211769813. The cubic root of 21424134 is about 277.7374382073.

Adding to 21424134 its reverse (43142412), we get a palindrome (64566546).

The spelling of 21424134 in words is "twenty-one million, four hundred twenty-four thousand, one hundred thirty-four".