21434938 has 16 divisors (see below), whose sum is σ = 37160640. Its totient is φ = 9082656.

The previous prime is 21434921. The next prime is 21434939. The reversal of 21434938 is 83943412.

It is not an unprimeable number, because it can be changed into a prime (21434939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7356 + ... + 9847.

It is an arithmetic number, because the mean of its divisors is an integer number (2322540).

Almost surely, 2^21434938 is an apocalyptic number.

21434938 is a deficient number, since it is larger than the sum of its proper divisors (15725702).

21434938 is a wasteful number, since it uses less digits than its factorization.

21434938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17301.

The product of its digits is 20736, while the sum is 34.

The square root of 21434938 is about 4629.7881161021. The cubic root of 21434938 is about 277.7841172005.

The spelling of 21434938 in words is "twenty-one million, four hundred thirty-four thousand, nine hundred thirty-eight".