21259842 has 32 divisors (see below), whose sum is σ = 44729280. Its totient is φ = 6726720.

The previous prime is 21259829. The next prime is 21259873. The reversal of 21259842 is 24895212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9613 + ... + 11615.

It is an arithmetic number, because the mean of its divisors is an integer number (1397790).

Almost surely, 2^21259842 is an apocalyptic number.

21259842 is an abundant number, since it is smaller than the sum of its proper divisors (23469438).

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

21259842 is a wasteful number, since it uses less digits than its factorization.

21259842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2098.

The product of its digits is 11520, while the sum is 33.

The square root of 21259842 is about 4610.8396198523. The cubic root of 21259842 is about 277.0256680546.

The spelling of 21259842 in words is "twenty-one million, two hundred fifty-nine thousand, eight hundred forty-two".