21300587 has 16 divisors (see below), whose sum is σ = 27475200. Its totient is φ = 16023840.

The previous prime is 21300583. The next prime is 21300619. The reversal of 21300587 is 78500312.

It is not a de Polignac number, because 21300587 - 2² = 21300583 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21300583) 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 15 ways as a sum of consecutive naturals, for example, 2537 + ... + 7002.

It is an arithmetic number, because the mean of its divisors is an integer number (1717200).

Almost surely, 2^21300587 is an apocalyptic number.

21300587 is a deficient number, since it is larger than the sum of its proper divisors (6174613).

21300587 is a wasteful number, since it uses less digits than its factorization.

21300587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9586.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 21300587 is about 4615.2558975641. The cubic root of 21300587 is about 277.2025305739.

Adding to 21300587 its reverse (78500312), we get a palindrome (99800899).

The spelling of 21300587 in words is "twenty-one million, three hundred thousand, five hundred eighty-seven".