21000585 has 8 divisors (see below), whose sum is σ = 33600960. Its totient is φ = 11200304.

The previous prime is 21000583. The next prime is 21000589. The reversal of 21000585 is 58500012.

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 21000585 - 2¹ = 21000583 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21000583) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 700005 + ... + 700034.

It is an arithmetic number, because the mean of its divisors is an integer number (4200120).

Almost surely, 2^21000585 is an apocalyptic number.

It is an amenable number.

21000585 is a deficient number, since it is larger than the sum of its proper divisors (12600375).

21000585 is a wasteful number, since it uses less digits than its factorization.

21000585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1400047.

The product of its (nonzero) digits is 400, while the sum is 21.

The square root of 21000585 is about 4582.6395232442. The cubic root of 21000585 is about 275.8949794725.

Adding to 21000585 its reverse (58500012), we get a palindrome (79500597).

The spelling of 21000585 in words is "twenty-one million, five hundred eighty-five", and thus it is an aban number.