21084329 has 8 divisors (see below), whose sum is σ = 24124800. Its totient is φ = 18050976.

The previous prime is 21084317. The next prime is 21084377. The reversal of 21084329 is 92348012.

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

It is a cyclic number.

It is not a de Polignac number, because 21084329 - 2⁴ = 21084313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21084379) 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, 8717 + ... + 10869.

It is an arithmetic number, because the mean of its divisors is an integer number (3015600).

Almost surely, 2^21084329 is an apocalyptic number.

It is an amenable number.

21084329 is a deficient number, since it is larger than the sum of its proper divisors (3040471).

21084329 is a wasteful number, since it uses less digits than its factorization.

21084329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3559.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 21084329 is about 4591.7675246031. The cubic root of 21084329 is about 276.2612217413.

The spelling of 21084329 in words is "twenty-one million, eighty-four thousand, three hundred twenty-nine".