21424138 has 8 divisors (see below), whose sum is σ = 32389632. Its totient is φ = 10627596.

The previous prime is 21424129. The next prime is 21424159. The reversal of 21424138 is 83142412.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41920 + ... + 42427.

It is an arithmetic number, because the mean of its divisors is an integer number (4048704).

Almost surely, 2^21424138 is an apocalyptic number.

21424138 is a deficient number, since it is larger than the sum of its proper divisors (10965494).

21424138 is a wasteful number, since it uses less digits than its factorization.

21424138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84476.

The product of its digits is 1536, while the sum is 25.

The square root of 21424138 is about 4628.6216090754. The cubic root of 21424138 is about 277.7374554923.

The spelling of 21424138 in words is "twenty-one million, four hundred twenty-four thousand, one hundred thirty-eight".