21675305 has 8 divisors (see below), whose sum is σ = 26043072. Its totient is φ = 17318448.

The previous prime is 21675301. The next prime is 21675331. The reversal of 21675305 is 50357612.

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 21675305 - 2² = 21675301 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21675301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2594 + ... + 7076.

It is an arithmetic number, because the mean of its divisors is an integer number (3255384).

Almost surely, 2^21675305 is an apocalyptic number.

It is an amenable number.

21675305 is a deficient number, since it is larger than the sum of its proper divisors (4367767).

21675305 is an equidigital number, since it uses as much as digits as its factorization.

21675305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5455.

The product of its (nonzero) digits is 6300, while the sum is 29.

The square root of 21675305 is about 4655.6744946356. The cubic root of 21675305 is about 278.8185980099.

The spelling of 21675305 in words is "twenty-one million, six hundred seventy-five thousand, three hundred five".