21424043 has 8 divisors (see below), whose sum is σ = 21772800. Its totient is φ = 21077608.

The previous prime is 21424027. The next prime is 21424049. The reversal of 21424043 is 34042412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21424043 - 2⁴ = 21424027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21424049) 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, 29438 + ... + 30156.

It is an arithmetic number, because the mean of its divisors is an integer number (2721600).

Almost surely, 2^21424043 is an apocalyptic number.

21424043 is a deficient number, since it is larger than the sum of its proper divisors (348757).

21424043 is an equidigital number, since it uses as much as digits as its factorization.

21424043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1161.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 21424043 is about 4628.6113468296. The cubic root of 21424043 is about 277.7370449725.

Adding to 21424043 its reverse (34042412), we get a palindrome (55466455).

The spelling of 21424043 in words is "twenty-one million, four hundred twenty-four thousand, forty-three".