21459234 has 16 divisors (see below), whose sum is σ = 42972480. Its totient is φ = 7144080.

The previous prime is 21459211. The next prime is 21459239. The reversal of 21459234 is 43295412.

It is not an unprimeable number, because it can be changed into a prime (21459239) 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, 4452 + ... + 7920.

It is an arithmetic number, because the mean of its divisors is an integer number (2685780).

Almost surely, 2^21459234 is an apocalyptic number.

21459234 is an abundant number, since it is smaller than the sum of its proper divisors (21513246).

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

21459234 is a wasteful number, since it uses less digits than its factorization.

21459234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4505.

The product of its digits is 8640, while the sum is 30.

The square root of 21459234 is about 4632.4112511736. The cubic root of 21459234 is about 277.8890315006.

The spelling of 21459234 in words is "twenty-one million, four hundred fifty-nine thousand, two hundred thirty-four".