21300547 has 4 divisors (see below), whose sum is σ = 21360240. Its totient is φ = 21240856.

The previous prime is 21300527. The next prime is 21300551. The reversal of 21300547 is 74500312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21300547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21300527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29308 + ... + 30025.

It is an arithmetic number, because the mean of its divisors is an integer number (5340060).

Almost surely, 2^21300547 is an apocalyptic number.

21300547 is a deficient number, since it is larger than the sum of its proper divisors (59693).

21300547 is an equidigital number, since it uses as much as digits as its factorization.

21300547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59692.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 21300547 is about 4615.2515641079. The cubic root of 21300547 is about 277.2023570558.

Adding to 21300547 its reverse (74500312), we get a palindrome (95800859).

The spelling of 21300547 in words is "twenty-one million, three hundred thousand, five hundred forty-seven".