21842424 has 24 divisors (see below), whose sum is σ = 59156760. Its totient is φ = 7280784.

The previous prime is 21842393. The next prime is 21842441. The reversal of 21842424 is 42424812.

21842424 is a `hidden beast` number, since 218 + 424 + 24 = 666.

It is a tau number, because it is divible by the number of its divisors (24).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a nude number because it is divisible by every one of its digits.

21842424 is a modest number, since divided by 2424 gives 2184 as remainder.

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, 151612 + ... + 151755.

It is an arithmetic number, because the mean of its divisors is an integer number (2464865).

Almost surely, 2^21842424 is an apocalyptic number.

21842424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21842424 is an abundant number, since it is smaller than the sum of its proper divisors (37314336).

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

21842424 is a wasteful number, since it uses less digits than its factorization.

21842424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303379 (or 303372 counting only the distinct ones).

The product of its digits is 4096, while the sum is 27.

The square root of 21842424 is about 4673.5879150819. The cubic root of 21842424 is about 279.5333383172.

The spelling of 21842424 in words is "twenty-one million, eight hundred forty-two thousand, four hundred twenty-four".